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1.
Arch Orthop Trauma Surg ; 143(6): 3173-3181, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36053291

ABSTRACT

INTRODUCTION: Femoral neck fractures (FNF) are one of the most frequent fractures among elderly patients and commonly require surgical treatment. Bipolar hip hemiarthroplasty (BHHA) is mostly performed in these cases. MATERIAL AND METHODS: In the present retrospective study geriatric patients with FNF (n = 100) treated either by anterior minimal-invasive surgery (AMIS; n = 50) or lateral conventional surgery (LCS; n = 50) were characterized (age at the time of surgery, sex, health status/ASA score, walking distance and need for walking aids before the injury) and intraoperative parameters (duration of surgery, blood loss, complications), as well as postoperative functional performance early (duration of in-patient stay, radiological leg length discrepancy, ability to full weight-bearing, mobilization with walking aids) and 12 months (radiological signs of sintering, clinical parameters, complication rate) after surgery were analyzed. RESULTS: Patients in the AMIS group demonstrated a reduced blood loss intraoperatively, while the duration of surgery and complication rates did not differ between the two groups. Further, more patients in the AMIS group achieved full weight-bearing of the injured leg and were able to walk with a rollator or less support during their in-patient stay. Of interest, patients in the AMIS group achieved this level of mobility earlier than those of the LCS group, although their walking distance before the acute injury was reduced. Moreover, patients of the AMIS group showed equal leg lengths postoperatively more often than patients of the LCS group. No significant differences in functional and surgery-related performance could be observed between AMIS and LCS group at 12 months postoperatively. CONCLUSIONS: In conclusion, geriatric patients treated by AMIS experience less surgery-related strain and recover faster in the early postoperative phase compared to LCS after displaced FNF. Hence, AMIS should be recommended for BHHA in these vulnerable patients.


Subject(s)
Arthroplasty, Replacement, Hip , Femoral Neck Fractures , Hemiarthroplasty , Humans , Aged , Retrospective Studies , Femoral Neck Fractures/surgery , Walking , Treatment Outcome
2.
J Prev Alzheimers Dis ; 9(3): 542-549, 2022.
Article in English | MEDLINE | ID: mdl-35841255

ABSTRACT

New therapies that address the underlying pathophysiology of Alzheimer's Disease (AD), coupled with the growth of the AD population, will transform the AD care pathway and present significant challenges to health systems. We explored real-world challenges health systems may face in delivering potential new AD therapies with diverse stakeholders. Key challenges in care included integrating primary care providers into assessment and management, availability of memory care specialists, understanding payment and coverage issues and training mid-level providers to help coordinate care and serve as a shared resource across the system. This input informed a novel Site Readiness Framework for AD, comprising self-assessment exercises to identify health system capabilities and gaps and a framework of core strategies and responsive tools to help prepare to integrate new AD therapies. These resources may help health systems improve readiness to modify care pathways to integrate new therapies for AD.


Subject(s)
Alzheimer Disease , Alzheimer Disease/therapy , Humans
3.
Eur J Trauma Emerg Surg ; 48(5): 3757-3764, 2022 Oct.
Article in English | MEDLINE | ID: mdl-34618166

ABSTRACT

BACKGROUND: Various plate shapes and implant configurations are used for stabilization of acetabulum fractures via anterior approaches. Little is known about the biomechanical stability of a two-dimensionally shaped "conventional" plate ("J-Plate"-JP) in comparison to three-dimensionally shaped plate configurations (3DP). In addition, the augmentary effect of an infra-acetabular lag-screw (IACS) fixation for anterior column and posterior hemi-transverse acetabulum fractures has not been clarified in comparison of JP and 3DP constructs. This study analyzed the difference between the biomechanical stability of JP compared to 3DP and the role of an IACS in a standardized acetabular fracture model in a single-leg stance loading configuration. METHODS: In an artificial bone substitute pelvis model (Synbone© Malans, Switzerland), a typical and standardized fracture pattern (anterior column and posterior hemi-transverse) was created with osteotomy jigs. After anatomic reduction the stabilization was performed using JP or 3DP. Eight pelvises per group were axially loaded in a single-leg stance model up to 400 N. After the load cycle, an additional infra-acetabular screw was placed and the measurement repeated. Fragment displacement was recorded by an optical tracking system (Optitrack Prime 13®, Corvallis, USA). RESULTS: In the pure placement, 3DP provided significantly superior stability when compared to JP. Augmentation of JP by IACS increased the stability significantly, up to the level of 3DP alone, whereas augmentation of the 3DP did not result in further increase of overall stability. CONCLUSION: The anatomically shaped plate alone provides a superior biomechanical stability in fixation of an anterior column and posterior hemi-transverse fracture model. In a JP fixation the augmentation by IACS provides similar strength as the anatomically shaped 3DP. By use of the anatomically shaped 3DP the need of a clinically risky application of IACS might be avoidable. LEVEL OF EVIDENCE: IV, Experimental study.


Subject(s)
Bone Substitutes , Fractures, Bone , Hip Fractures , Spinal Fractures , Acetabulum/injuries , Acetabulum/surgery , Biomechanical Phenomena , Bone Plates , Bone Screws , Fracture Fixation, Internal/methods , Fractures, Bone/diagnostic imaging , Fractures, Bone/surgery , Humans
4.
J Phys Condens Matter ; 33(48)2021 Sep 21.
Article in English | MEDLINE | ID: mdl-34399408

ABSTRACT

Blue phosphorene (BlueP) is a novel two-dimensional material that shares properties with black phosphorene and is potentially even more interesting for opto-electronic applications because of its layer dependent wide band gap of ≈ 2 to 3 eV and superior charge carrier mobility. It was first fabricated on Au(111), where, however, a network consisting of BlueP subunits and Au-linker atoms is formed. The physical properties of such an arrangement strongly differ from a freestanding BlueP monolayer. Here, we report on the growth of epitaxial BlueP on the Au(100) surface, which is an interesting alternative when aiming at quasi-freestanding BlueP domains. We find two different phosphorus phases by means of scanning tunneling microscopy and distortion-corrected low-energy electron diffraction. In the low coverage regime, we observe a commensurate (2 × 2) phase, whereas for higher coverage, a nearly hexagonal structure is formed. For the latter, the lattice parameters measured via atomically resolved scanning tunneling hydrogen microscopy closely resemble those of freestanding BlueP, and the typical height modulation of the phosphorus atoms is verified in our layers by means of x-ray photoelectron diffraction. We further analyze the chemical and electronic properties of these films by means of x-ray and (angle resolved) ultraviolet photoelectron spectroscopy.

5.
Front Bioeng Biotechnol ; 9: 809397, 2021.
Article in English | MEDLINE | ID: mdl-35087807

ABSTRACT

Deficient angiogenesis and disturbed osteogenesis are key factors for the development of nonunions. Mineral-coated microparticles (MCM) represent a sophisticated carrier system for the delivery of vascular endothelial growth factor (VEGF) and bone morphogenetic protein (BMP)-2. In this study, we investigated whether a combination of VEGF- and BMP-2-loaded MCM (MCM + VB) with a ratio of 1:2 improves bone repair in non-unions. For this purpose, we applied MCM + VB or unloaded MCM in a murine non-union model and studied the process of bone healing by means of radiological, biomechanical, histomorphometric, immunohistochemical and Western blot techniques after 14 and 70 days. MCM-free non-unions served as controls. Bone defects treated with MCM + VB exhibited osseous bridging, an improved biomechanical stiffness, an increased bone volume within the callus including ongoing mineralization, increased vascularization, and a histologically larger total periosteal callus area consisting predominantly of osseous tissue when compared to defects of the other groups. Western blot analyses on day 14 revealed a higher expression of osteoprotegerin (OPG) and vice versa reduced expression of receptor activator of NF-κB ligand (RANKL) in bone defects treated with MCM + VB. On day 70, these defects exhibited an increased expression of erythropoietin (EPO), EPO-receptor and BMP-4. These findings indicate that the use of MCM for spatiotemporal controlled delivery of VEGF and BMP-2 shows great potential to improve bone healing in atrophic non-unions by promoting angiogenesis and osteogenesis as well as reducing early osteoclast activity.

6.
Chirurg ; 89(12): 1009-1012, 2018 Dec.
Article in German | MEDLINE | ID: mdl-30054641

ABSTRACT

Work-life balance is a commonly used term that appears in different contexts and has a different meaning for many colleagues. Unfortunately, however, it is often used as a negative, simplified term to describe the assumed attitude of young surgeons towards work and a medical career, even though this is not universally applicable. As the representatives for Young Surgeons of the German Society of Surgery the aim of this article is to present our thoughts on the issue and associated problems and provide a differentiated outline for discussion.


Subject(s)
Surgeons , Work-Life Balance
7.
Langmuir ; 33(28): 6978-6984, 2017 07 18.
Article in English | MEDLINE | ID: mdl-28602078

ABSTRACT

The molecular donor tetraphenyldibenzoperiflanthene (DBP) forms coverage-dependent superstructures on Au(111). At submonolayer coverage, the molecules align parallel to each other. They arrange in row-like structures, which exhibit a nearly rectangular primitive unit cell. By contrast, the molecular monolayer is characterized by a herringbone-type DBP arrangement spanned by an almost square unit cell containing two molecules. Both superstructures occur simultaneously in a narrow coverage range close to completion of the molecular monolayer. The adsorbate-substrate interaction is similar to other physisorbed molecular films on Au(111), but differs for the two adsorption phases as inferred from the different modification of the Au(111) surface reconstruction. Structural properties were consistently probed in real and reciprocal space by scanning tunneling microscopy and low-energy electron diffraction, respectively.

8.
Clin Radiol ; 72(9): 739-744, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28395916

ABSTRACT

AIM: To define practical limitations of diagnostic image quality for recently introduced turbo high-pitch scan mode (THP) in third-generation dual-source computed tomography (CT). MATERIALS AND METHODS: Two hundred and twenty-nine consecutive patients undergoing CT coronary angiography were included in this retrospective single-centre analysis. A contrast-enhanced volume dataset was acquired in THP. Image quality of coronary segments was classified as diagnostic or non-diagnostic by three blinded readers. Segments were stated as non-diagnostic if at least one of three readers could neither exclude nor confirm significant stenoses. Multivariable logistic regression was used to assess relationships between number of non-diagnostic segments and common influencing factors. RESULTS: Median effective radiation dose was 0.6 (interquartile range [IQR], 0.4-0.8) mSv overall and 0.3 (IQR, 0.3-0.4) mSv in the 70 kV subgroup of this middle aged, predominantly pre-obese cohort (age: 61 [IQR, 52-67] years; body mass index [BMI]: 26 [IQR, 23-29] kg/m2) with a low-moderate median Agatston score (AS) 0 (IQR, 0-70). Diagnostic image quality was found in 98.1% of 3,678 coronary segments. AS was independently associated with diagnostic image quality (B=0.34; p=0.02), whereas heart rate, BMI, and presence of arrhythmia were not. The portion of diagnostic coronary segments decreased slightly in obese patients with heart rates >65 beats/min and dropped significantly in patients with an AS >600 (p=0.003). CONCLUSION: THP enables CT coronary angiography with minimal radiation exposure and is most appropriate in non-obese patients with stable sinus rhythm ≤65 beats/min and a calcium score ≤600.


Subject(s)
Computed Tomography Angiography/methods , Coronary Stenosis/diagnostic imaging , Aged , Cardiac-Gated Imaging Techniques , Contrast Media , Coronary Angiography/methods , Female , Humans , Iopamidol/analogs & derivatives , Male , Middle Aged , Radiation Exposure , Radiographic Image Interpretation, Computer-Assisted , Retrospective Studies
9.
Zentralbl Chir ; 142(2): 194-198, 2017 Apr.
Article in German | MEDLINE | ID: mdl-26679716

ABSTRACT

Background: No current studies regarding saw injuries have been published in German literature for quite some time. Despite awareness measures and safety instructions, saw accidents along with crush injuries are the most common causes of severe hand injuries. Approximately 12,000 circular saw injuries occur in Germany each year. Since professional providers have increased prices due to the rising energy costs and a wide range of different home appliance saws are available, increasing use has been made of portable circular saws in the do-it-yourself market sector. Patients and methods: At our hospital, we evaluated the data of 51 male patients with saw injuries. The present study investigated factors that may contribute to accidents involving saws. Results: 80 % of the accidents occurred at home, usually on weekends or after work. 51 % of the accidents happened while patients cut firewood. In 84 % of the cases, an electric table saw was used. The majority of severe hand injuries were sustained with lower priced saws. Injuries occurred most frequently between 11 a. m. and 2 p. m., primarily with injuries to bones, tendons, blood vessels and nerves. Replantable amputations or partial amputations occured rarely. In 37 % of the patients, anatomical reconstruction using osteosynthesis and/or microsurgical techniques was performed successfully. Conclusions: Saw injuries to the hand are sustained almost exclusively by men. Serious injuries from low-priced table saws and due to the lack of protective covering are predominant. Preventive measures and mandatory training could reduce the number of saw injuries in the years to come. The results obtained by us largely confirm the data from previous publications.


Subject(s)
Accidents, Home/statistics & numerical data , Accidents, Occupational/statistics & numerical data , Hand Injuries/epidemiology , Hand Injuries/etiology , Accidents, Home/prevention & control , Accidents, Occupational/prevention & control , Adult , Aged , Cross-Sectional Studies , Equipment Safety , Germany , Hand Injuries/prevention & control , Humans , Injury Severity Score , Male , Middle Aged , Protective Devices , Risk Factors , Statistics as Topic , Young Adult
10.
Herz ; 40(7): 959-65, 2015 Nov.
Article in German | MEDLINE | ID: mdl-26525523

ABSTRACT

Sympathovagal imbalance plays an important role in the progression of heart failure with reduced ejection fraction. Baroreflex activation therapy (BAT), i. e. electrical stimulation of baroreceptors located at the carotid sinus, can reduce sympathetic and enhance parasympathetic tone. Large animal studies on BAT demonstrated improvements in cardiac function, arrhythmogenic risk and a survival benefit compared to untreated controls. The recently published Neo Randomized Heart Failure Study, the first multicenter, randomized and controlled trial of optimal medical and device therapy alone or plus BAT in patients with a left ventricular ejection fraction ≤ 35 %, demonstrated a reasonable safety profile of BAT in this severely ill patient population and no relevant interactions with other devices. The study found significant improvements in the New York Heart Association (NYHA) class of heart failure, quality of life as well as 6 min walking distance and data pointed to a reduction in hospitalization rates. Moreover, N-terminal pro-brain natriuretic peptide (NT-proBNP) levels were significantly reduced. This review gives an overview on BAT for the treatment of heart failure with reduced ejection fraction, from the rationale and animal experiments to the most recent clinical data and future perspectives.


Subject(s)
Baroreflex , Electric Stimulation Therapy/methods , Heart Failure/complications , Heart Failure/prevention & control , Ventricular Dysfunction, Left/complications , Ventricular Dysfunction, Left/prevention & control , Chronic Disease , Evidence-Based Medicine , Heart Failure/diagnosis , Humans , Pressoreceptors , Technology Assessment, Biomedical , Treatment Outcome , Ventricular Dysfunction, Left/diagnosis
11.
Eur J Pain ; 19(4): 503-7, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25115658

ABSTRACT

Complex regional pain syndrome is a severe complication following trauma that is associated with vasomotor, sudomotor and sensory disturbances in an affected limb or region of the body. The exact physiopathology is not fully understood yet. Recently, autoantibody findings suggested an immune-mediated physiopathology of the disease. We here describe two otherwise treatment-resistant patients with complex regional pain syndrome and high-titre beta2 adrenergic receptor autoantibodies, who did respond to plasmapheresis. Both patients showed strong improvement of pain and autonomic symptoms measured by impairment level sum score.


Subject(s)
Complex Regional Pain Syndromes/therapy , Pain Management , Plasmapheresis , Adult , Complex Regional Pain Syndromes/diagnosis , Female , Humans , Middle Aged , Pain/diagnosis , Pain Measurement , Plasmapheresis/methods , Treatment Outcome
12.
Water Res ; 61: 162-70, 2014 Sep 15.
Article in English | MEDLINE | ID: mdl-24911562

ABSTRACT

Titration methodologies have been used for the many years for low cost routine monitoring of full scale anaerobic digestion plants. These methodologies have been correlated to indicate the carbonate alkalinity and the volatile fatty acids (VFA) content within digesters. Two commonly used two end-point titration methods were compared using a dataset of 154 samples from energy crop and animal slurry digestates and were shown to be inaccurate in the estimation of tVFA. Using this dataset correlated with HPLC VFA analysis, two empirical bivariate linear regression equations were derived, where the validation dataset showed an absolute tVFA mean error improvement from ±3386 and ±3324 mg kg(-1) tVFA to ±410 and ±286 mg kg(-1) tVFA, respectively. The same equation was then applied to a food waste dataset where an absolute tVFA mean error was improved from ±3828 to ±576 mg kg(-1) tVFA. The newly derived titration equations can provide greater confidence in digester performance monitoring and are tools that can improve digester management.


Subject(s)
Fatty Acids, Volatile/analysis , Manure/analysis , Refuse Disposal/methods , Solid Waste/analysis , Anaerobiosis , Chromatography, High Pressure Liquid , Models, Theoretical
14.
Biomed Tech (Berl) ; 58 Suppl 12013 08.
Article in English | MEDLINE | ID: mdl-24043041
15.
Nat Commun ; 4: 2263, 2013.
Article in English | MEDLINE | ID: mdl-23948952

ABSTRACT

In recent years, the use of information principles to understand quantum correlations has been very successful. Unfortunately, all principles considered so far have a bipartite formulation, but intrinsically multipartite principles, yet to be discovered, are necessary for reproducing quantum correlations. Here we introduce local orthogonality, an intrinsically multipartite principle stating that events involving different outcomes of the same local measurement must be exclusive or orthogonal. We prove that it is equivalent to no-signalling in the bipartite scenario but more restrictive for more than two parties. By exploiting this non-equivalence, it is then demonstrated that some bipartite supra-quantum correlations do violate the local orthogonality when distributed among several parties. Finally, we show how its multipartite character allows revealing the non-quantumness of correlations for which any bipartite principle fails. We believe that local orthogonality is a crucial ingredient for understanding no-signalling and quantum correlations.

17.
Am J Ophthalmol ; 155(1): 183-189.e1, 2013 Jan.
Article in English | MEDLINE | ID: mdl-22967869

ABSTRACT

PURPOSE: To evaluate the incidence of optic neuritis (ON) in patients using anti-tumor necrosis factor (TNF) alpha therapy. DESIGN: Retrospective, population-based cohort study. METHODS: We identified new users of anti-TNF therapy (etanercept, infliximab, or adalimumab) or nonbiologic disease-modifying antirheumatic drugs (DMARDs) during 2000-2007 from the following data sources: Kaiser Permanente Northern California, Pharmaceutical Assistance Contract for the Elderly, Tennessee Medicaid, and National Medicaid/Medicare. Within this cohort, we used validated algorithms to identify ON cases occurring after onset of new drug exposure. We then calculated and compared ON incidence rates between exposure groups. RESULTS: We identified 61 227 eligible inflammatory disease patients with either new anti-TNF or new nonbiologic DMARD use. Among this cohort, we found 3 ON cases among anti-TNF new users, occurring a median of 123 days (range, 37-221 days) after anti-TNF start. The crude incidence rate of ON across all disease indications among anti-TNF new users was 10.4 (95% CI 3.3-32.2) cases per 100 000 person-years. In a sensitivity analysis considering current or past anti-TNF or DMARD use, we identified a total of 6 ON cases: 3 among anti-TNF users and 3 among DMARD users. Crude ON rates were similar among anti-TNF and DMARD groups: 4.5 (95% CI 1.4-13.8) and 5.4 (95% CI 1.7-16.6) per 100 000 person-years, respectively. CONCLUSION: Optic neuritis is rare among those who initiate anti-TNF therapy and occurs with similar frequency among those with nonbiologic DMARD exposure.


Subject(s)
Antirheumatic Agents/administration & dosage , Antirheumatic Agents/adverse effects , Optic Neuritis/epidemiology , Tumor Necrosis Factor-alpha/antagonists & inhibitors , Adalimumab , Adult , Algorithms , Antibodies, Monoclonal/administration & dosage , Antibodies, Monoclonal/adverse effects , Antibodies, Monoclonal, Humanized/administration & dosage , Antibodies, Monoclonal, Humanized/adverse effects , Cohort Studies , Databases, Factual , Etanercept , Female , Humans , Immunoglobulin G/administration & dosage , Immunoglobulin G/adverse effects , Incidence , Infliximab , Male , Middle Aged , Optic Neuritis/chemically induced , Optic Neuritis/diagnosis , Receptors, Tumor Necrosis Factor/administration & dosage , Retrospective Studies , Risk Assessment
18.
Diabetes Metab Res Rev ; 29(1): 25-32, 2013 Jan.
Article in English | MEDLINE | ID: mdl-22887834

ABSTRACT

BACKGROUND: Physical activity remains a valuable prevention for metabolic disease. The effects of Nordic walking on cardiovascular risk factors were determined in overweight individuals with normal or disturbed glucose regulation. METHODS: We included 213 individuals, aged 60 ± 5.3 years and with body mass index (BMI) of 30.2 ± 3.8 kg/m(2); of these, 128 had normal glucose tolerance (NGT), 35 had impaired glucose tolerance (IGT) and 50 had type 2 diabetes mellitus (T2DM). Participants were randomized to unaltered physical activity or to 5 h per week of Nordic walking with poles, for a 4-month period. Dietary habits were unaltered. BMI, waist circumference, blood pressure, glucose tolerance, clinical chemistry, maximal oxygen uptake (peak VO(2)) and self-reported physical activity (questionnaire) were assessed at the time of inclusion and after 4 months. The participants in the exercise-intervention group kept a walking diary. RESULTS: In the NGT exercise group, self-reported physical activity increased markedly, and body weight (-2.0 ± 3.8 kg), BMI (-0.8 ± 1.4 kg/m(2)) and waist circumference (-4.9 ± 4.4 cm) (mean ± SD) decreased. Exercise power output (12.9 ± 9.9 W) and peak VO(2) (2.7 ± 2.8 mL/kg/min) increased in the IGT exercise group. More cardiovascular risk factors were improved after exercise intervention in people with NGT compared with those with IGT or T2DM. Exercise capacity improved significantly in all three groups of participants who reported at least 80% compliance with the scheduled exercise. CONCLUSIONS: Nordic walking improved anthropometric measurements and exercise capacity. However, unsupervised Nordic walking may not provide a sufficient increase in exercise intensity to achieve ultimate health-promoting benefits on the cardiovascular parameters assessed in this study, particularly for those with disturbed glucose regulation.


Subject(s)
Cardiovascular Diseases/etiology , Diabetes Mellitus, Type 2/therapy , Exercise Therapy/methods , Glucose Intolerance/therapy , Overweight/therapy , Walking/physiology , Aged , Blood Pressure/physiology , Body Mass Index , Cardiovascular Diseases/prevention & control , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/physiopathology , Female , Glucose Intolerance/complications , Glucose Intolerance/physiopathology , Glucose Tolerance Test , Humans , Life Style , Male , Middle Aged , Motor Activity/physiology , Overweight/complications , Overweight/physiopathology , Oxygen Consumption/physiology , Surveys and Questionnaires , Treatment Outcome , Waist Circumference/physiology
20.
Nature ; 481(7379): 51-4, 2011 Dec 14.
Article in English | MEDLINE | ID: mdl-22170607

ABSTRACT

Measurements of stellar orbits provide compelling evidence that the compact radio source Sagittarius A* at the Galactic Centre is a black hole four million times the mass of the Sun. With the exception of modest X-ray and infrared flares, Sgr A* is surprisingly faint, suggesting that the accretion rate and radiation efficiency near the event horizon are currently very low. Here we report the presence of a dense gas cloud approximately three times the mass of Earth that is falling into the accretion zone of Sgr A*. Our observations tightly constrain the cloud's orbit to be highly eccentric, with an innermost radius of approach of only ∼3,100 times the event horizon that will be reached in 2013. Over the past three years the cloud has begun to disrupt, probably mainly through tidal shearing arising from the black hole's gravitational force. The cloud's dynamic evolution and radiation in the next few years will probe the properties of the accretion flow and the feeding processes of the supermassive black hole. The kilo-electronvolt X-ray emission of Sgr A* may brighten significantly when the cloud reaches pericentre. There may also be a giant radiation flare several years from now if the cloud breaks up and its fragments feed gas into the central accretion zone.

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