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1.
PeerJ ; 11: e15205, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37041974

RESUMEN

Background: Quantitative Ultrasound (QUS) methods have been widely used to assess estimated bone density. This study aimed to assess changes in estimated bone density in association with changes in body composition, physical activity, and anthropometry. Methods: We examined changes in anthropometry, body composition, and physical activity associated with changes in estimated bone mineral density (measured using quantitative ultrasound with a heel ultrasound device indicating broadband ultrasound attenuation BUA and speed of sound SOS) in a follow-up sample of n = 73 young men at the beginning and again 18 weeks later at the end of basic military training. Results: At the end of the basic training, the subjects were on average significantly heavier (+1.0%), slightly taller (+0.5%) and had a higher fat mass (+6.6%) and grip strength (+8.6%). A significant decrease in mean physical activity (-49.5%) and mean estimated bone density calculated with BUA (-7.5%) was observed in the paired t-test. The results of the multivariable linear regressions (backward selection) show that changes in skeletal muscle mass (delta = 2nd measurement minus 1st measurement) have negative and body weight (delta) have positive association with the speed of sound SOS (delta), while fat mass (delta) and physical activity (delta) had the strongest negative associations with estimated bone mineral density (delta). In particular, we found a negative association between fat mass (delta) and estimated bone mineral density (delta, estimated with BUA). Conclusion: Our study suggests that estimated bone density from the calcaneus can change within a few months even in young and mostly healthy individuals, depending upon physical activity levels and other co-factors. Further studies including other troop types as control groups as well as on women should follow in order to investigate this public health relevant topic in more depth. To what extent the estimated bone density measurement with quantitative ultrasound is clinically relevant needs to be investigated in further studies.


Asunto(s)
Densidad Ósea , Calcáneo , Personal Militar , Ultrasonografía , Femenino , Humanos , Masculino , Peso Corporal , Densidad Ósea/fisiología , Estudios de Seguimiento , Personal Militar/educación , Suiza , Talón/diagnóstico por imagen , Ultrasonografía/métodos , Calcáneo/diagnóstico por imagen , Educación
2.
PLoS One ; 16(4): e0250745, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33930057

RESUMEN

Computed tomography studies and histological analyses were performed on the mummified remains found in the Chehrabad salt mine in northwestern Iran. The ancient salt mummies are dated to the Achaemenid (550-330 BC) and Sassanid (3rd-7th century AD) time period and died in mining incidents. The aim of the study was to describe the radiological and histological findings of several ancient Iranian salt mummies with special interest in pathological and postmortem changes. The mummified remains show multiple traumatic alterations, such as fractures and signs of massive compression. Histological analyses can clearly differentiate soft tissue, however the preservation status is variable. These Iranian salt mummies are a rare example of the ancient Iranian population. The soft tissue and organs are well preserved, however in different degrees due to the varying conditions.


Asunto(s)
Momias/patología , Arqueología , Hueso Cortical/patología , Historia Antigua , Humanos , Irán , Momias/diagnóstico por imagen , Momias/historia , Faringe/patología , Cloruro de Sodio/química , Tomografía Computarizada por Rayos X
3.
Magn Reson Med ; 85(3): 1481-1492, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33009877

RESUMEN

PURPOSE: Evolutionary medicine aims to study disease development from a long-term perspective, and through the analysis of mummified tissue, timescales of several thousand years are unlocked. Due to the status of mummies as ancient relics, noninvasive techniques are preferable, and, currently, CT imaging is the most widespread method. However, CT images lack soft-tissue contrast, making complementary MRI data desirable. Unfortunately, the dehydrated nature and short T2 times of mummified tissues render them practically invisible to standard MRI techniques. Specialized short-T2 approaches have therefore been used, but currently suffer severe resolution limitations. The purpose of the present study is to improve resolution in MRI of mummified tissues. METHODS: The zero-TE-based hybrid filling technique, together with a high-performance magnetic field gradient, was used to image three ancient Egyptian mummified human body parts: a hand, a foot, and a head. A similar pairing has already been shown to increase resolution and image quality in MRI of short-T2 tissues. RESULTS: MRI images of yet unparalleled image quality were obtained for all samples, reaching isotropic resolutions of 0.6 mm and SNR values above 100. The same general features as present in CT images were depicted but with different contrast, particularly for regions containing embalming substances. CONCLUSION: Mummy MRI is a potentially valuable tool for (paleo)pathological studies, as well as for investigations into ancient mummification processes. The results presented here show sufficient improvement in the depiction of mummified tissues to clear new paths for the exploration of this field.


Asunto(s)
Momias , Egipto , Mano/anatomía & histología , Cabeza , Humanos , Imagen por Resonancia Magnética , Momias/diagnóstico por imagen
4.
Clin Anat ; 33(6): 860-871, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31943391

RESUMEN

Understanding natural and artificial postmortem alterations in different tissues of the human body is essential for bioarchaeology, paleogenetics, physical anthropology, forensic medicine, and many related disciplines. With this study, we tried to gain a better understanding of tissue alterations associated with the artificial mummification techniques of ancient Egypt, in particular for mummified visceral organs. We used several entire porcine organs and organ sections (liver, lung, stomach, ileum, and colon), which provided a close approximation to human organs. First, we dehydrated the specimens in artificial natron, before applying natural ointments, according to the ancient literary sources and recent publications. We periodically monitored the temperature, pH value, and weight of the specimens, in addition to radiodensity and volumetric measurements by clinical computed tomography and sampling for histological, bacteriological, and molecular analyses. After seven weeks, mummification was seen completed in all specimens. We observed a considerable loss of weight and volume, as well as similar courses in the decay of tissue architecture but varying levels of DNA degradation. Bacteriologically we did not detect any of the initially identified taxa in the samples by the end of the mummification process, nor any fungi. This feasibility study established an experimental protocol for future experiments modeling ancient Egyptian mummification of visceral organs using human specimens. Understanding desiccation and mummification processes in non-pathological tissues of specific visceral organs may help to identify and interpret disease-specific alterations in mummified tissues in ancient Egyptian canopic jars and organ packages contained in whole mummies.


Asunto(s)
Embalsamiento/métodos , Conservación de Tejido/métodos , Animales , Estudios de Factibilidad , Tracto Gastrointestinal/anatomía & histología , Hígado/anatomía & histología , Pulmón/anatomía & histología , Porcinos
5.
Anat Rec (Hoboken) ; 303(12): 3085-3095, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-31837087

RESUMEN

Artificial mummification has been used since antiquity and is best known from ancient Egypt. Despite ancient Egyptian mummies being studied for several decades, the mummification techniques of that time are not well understood. Modern mummification experiments involving animal and human tissues have contributed additional insights relevant to a broad field of research. In the current study, we present follow-up results of an experiment on artificial mummification, which began in 2009. A human leg was artificially mummified and monitored for almost a year with histological, molecular, and radiological techniques. Since then, it has remained in a dry, natron salt blend for 9 years. The current analyses show further progression of dehydration and tissue alterations, as well as DNA degradation, suggesting an ongoing process. Our results add new insights into the mechanisms of tissue mummification. Taking into account that the process is still ongoing, further research is required, including a re-evaluation of the human leg in the future.


Asunto(s)
Embalsamiento/métodos , Pierna/patología , Momias/patología , Humanos , Pierna/diagnóstico por imagen , Momias/diagnóstico por imagen , Tomografía Computarizada por Rayos X
6.
Sci Rep ; 9(1): 3390, 2019 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-30833736

RESUMEN

We used a robotic-based THz imaging system to investigate the sub-surface structure of an artificially mummified ancient Egyptian human left hand. The results obtained are compared to the results of a conventional CT and a micro-CT scan. Using such a robotic THz system promises new insights into the sub-surface structure of human remains. The depth resolution of the THz images exceeds the resolution of a conventional CT scan and is comparable with a micro-CT scan. The advantage of THz measurements over micro-CT scans is the fact that even comparatively large samples, like complete bodies, can be scanned. These would not fit into a conventional micro-CT scanner.


Asunto(s)
Mano/diagnóstico por imagen , Momias/diagnóstico por imagen , Robótica/métodos , Microtomografía por Rayos X/métodos , Egipto , Humanos , Reproducibilidad de los Resultados
7.
Clin Anat ; 32(1): 105-109, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30324624

RESUMEN

Frontal sinus osteoma is a relatively common finding in the modern clinical setting. Although, its paleopathological record is not in dispute, its presence in Ancient Egypt has never been clarified. The aim of this article is to contribute to the debate. An Egyptian mummy head from the Musée d'Éthnographie de Neuchâtel (Switzerland) was studied radiologically and the obtained evidence was contextualized in the wider frame of multidisciplinary paleopathology. A 128-slice CT scanner was used for further investigation; datasets were processed with OsiriX-64 bit (version 5.8.5), and multiplanar (MPR) and volumetric reconstructions were performed. A small hyperdense and well-defined structure, most likely an osteoma, was identified in the right frontal sinus. Frontal sinus osteoma definitely existed in Ancient Egypt. Finally, this represents the oldest case in anatomically modern humans so far reported. Clin. Anat.32:105-109, 2019. © 2018 Wiley Periodicals, Inc.


Asunto(s)
Seno Frontal/patología , Momias/patología , Osteoma/patología , Neoplasias Craneales/patología , Humanos
8.
PLoS One ; 11(11): e0166571, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27902731

RESUMEN

Queen Nefertari, the favourite Royal Consort of Pharaoh Ramses II (Ancient Egypt, New Kingdom, 19th Dynasty c. 1250 BC) is famous for her beautifully decorated tomb in the Valley of the Queens. Her burial was plundered in ancient times yet still many objects were found broken in the debris when the tomb was excavated. Amongst the found objects was a pair of mummified legs. They came to the Egyptian Museum in Turin and are henceforth regarded as the remains of this famous Queen, although they were never scientifically investigated. The following multidisciplinary investigation is the first ever performed on those remains. The results (radiocarbon dating, anthropology, paleopathology, genetics, chemistry and Egyptology) all strongly speak in favour of an identification of the remains as Nefertari's, although different explanations-albeit less likely-are considered and discussed. The legs probably belong to a lady, a fully adult individual, of about 40 years of age. The materials used for embalming are consistent with Ramesside mummification traditions and indeed all objects within the tomb robustly support the burial as of Queen Nefertari.


Asunto(s)
Embalsamiento/métodos , Pierna/anatomía & histología , Momias/historia , Paleopatología/métodos , Secuencia de Bases , ADN Mitocondrial/genética , Antiguo Egipto , Historia Antigua , Humanos , Datación Radiométrica , Análisis de Secuencia de ADN
10.
Magn Reson Med ; 75(2): 701-8, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25752671

RESUMEN

PURPOSE: To compare the three different short-echo time (TE) pulse sequences ultrashort echo time (UTE), point-wise encoding time reduction with radial acquisition (PETRA), and single point imaging (SPI) for MRI of ancient remains. METHODS: MRI of mummies is challenging due to the extremely low water content and the very short transverse relaxation times T2 *. To overcome the signal loss associated with the short T2 *, three pulse sequences with very short TEs were compared. MR images of an ancient mummified human hand were acquired at field strengths of 1.5 Tesla (T) and 3T using home-made solenoid Tx/Rx radiofrequency (RF) coils. RESULTS: In all MR images, tissues could be differentiated and anatomical structures such as bones and tendons were clearly identified. Skin with embalming resin was hyperintense in MRI, whereas it appeared iso-intense in computed tomography. PETRA has the highest signal to noise ratio. With UTE, short scan times and a homogeneous RF excitation can be achieved, and blurring is less pronounced than with PETRA. SPI shows no blurring artifacts; however, it requires long scan times. CONCLUSION: This work provided an initial analysis for the optimization of imaging protocols for paleoradiology studies with MRI, and, ultimately, for MRI of tissue with extremely short T2 *.


Asunto(s)
Mano/anatomía & histología , Imagen por Resonancia Magnética/métodos , Momias , Egipto , Humanos , Aumento de la Imagen/métodos
11.
PLoS One ; 10(7): e0131916, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26200778

RESUMEN

The mummies of Kha and his wife Merit were found intact in an undisturbed tomb in western Thebes near the ancient workers' village of Deir el-Medina. Previous MDCT (this abbreviation needs spelling out) investigations showed that the bodies of Kha and Merit did not undergo classical royal 18th Dynasty artificial mummification, which included removal of the internal organs. It was, therefore, concluded that the retention of the viscera in the body, combined with an absence of canopic jars in the burial chamber, meant the couple underwent a short and shoddy funerary procedure, despite their relative wealth at death. Nevertheless, all internal organs - brain, ocular bulbs/ocular nerves, thoracic and abdominal organs - showed a very good state of preservation, which contradicts the previous interpretation above. In order to better understand the type of mummification used to embalm these bodies, both wrapped mummies were reinvestigated using new generation X-ray imaging and chemical microanalyses Here we provide evidence that both individuals underwent a relatively high quality of mummification, fundamentally contradicting previous understanding. Elucidated "recipes", whose components had anti-bacterial and anti-insecticidal properties, were used to treat their bodies. The time and effort undoubtedly employed to embalm both Kha and Merit and the use of imported costly resins, notably Pistacia, do not support the previously held view that the two individuals were poorly mummified. Despite a lack of evisceration, the approach clearly allowed their in situ preservation as well as affording a fairly successful mummification.


Asunto(s)
Momias/diagnóstico por imagen , Momias/historia , Antiguo Egipto , Femenino , Historia Antigua , Humanos , Masculino , Radiografía
12.
Anat Rec (Hoboken) ; 298(6): 1135-43, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25998647

RESUMEN

During the last few years, terahertz (THz) imaging has been used to investigate artwork and historic artifacts. The application of THz imaging to mummy investigations is very attractive since it provides spectroscopic information over a broad frequency range and its radiation has proven to be harmless to human cells. However, compared with the current standard imaging methods in mummy imaging-X-ray and computed tomography (CT)--it remains a novel, emerging technique whose potential still needs to be fully evaluated. Here, ancient Egyptian mummified objects as well as a naturally mummified rat have been investigated by two different THz imaging systems: a broadband THz time domain imaging system and an electronic THz scanner. The obtained THz images are compared with conventional CT, X-ray, and magnetic resonance images. While the broadband THz time domain setup permits analyses of smaller samples, the electronic THz scanner allows the recording of data of thicker and larger samples at the expense of a limited spectral bandwidth. Terahertz imaging shows clear potential for mummy investigations, although currently CT imaging offers much higher spatial resolution. Furthermore, as commercial mobile THz scanners become available, THz imaging could be applied directly in museums or at excavation sites.


Asunto(s)
Momias/patología , Imágen por Terahertz , Animales , Humanos , Ratas
13.
Anat Rec (Hoboken) ; 298(6): 1162-74, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25998649

RESUMEN

Mummification leads to alteration of soft-tissue morphology. No research has focused specifically on differences in soft-tissue shrinkage depending on mummification type. This study evaluated whether soft-tissue alteration is dependent on type of mummification. A total of 17 human mummies have been investigated by computed tomography (CT). Samples included artificially embalmed ancient Egyptian mummies, naturally mummified South American corpses, ice mummies (including the Iceman, South Tyrol Museum of Archeology, Bolzano, Italy, ca. 3,300 BC), bog bodies and a desiccated mummy of possibly Asian provenance. The acquired data were compared to four contemporary bodies. The extent of soft-tissue shrinkage was evaluated using CT data. Shrinkage was defined as soft-tissue relative to area of bone (in number of voxels). Measurements were taken at 13 anatomically defined locations. Ice mummies show the highest degree of preservation. This finding is most likely explained due to frozen water within tissues. All other types of mummies show significantly (at P < 0.05) smaller relative area of preserved soft-tissue. Variation between different anatomical structures (e.g., upper lip vs. mid-femur) is significant, unlike variation within one compartment (e.g., proximal vs. distal humerus). Mummification type strongly affects the degree of soft-tissue alteration, surprisingly mostly independent of overall historical age. These results highlight the unique morphological impact of taphonomy on soft-tissue preservation and are of particular interest in tissue research as well as in forensics.


Asunto(s)
Huesos/diagnóstico por imagen , Momias/diagnóstico por imagen , Conservación de Tejido/métodos , Humanos , Radiografía , Humedales
14.
Am J Phys Anthropol ; 157(3): 519-25, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25916977

RESUMEN

Body height is an important factor in reconstructing health conditions and it serves as an indicator of socio-economic status. Researchers rely on ancient data to analyze evolutionary aspects of human health and its interrelation with environmental influences. This study presents body height estimates from all periods of ancient Egyptian history and compares the general population with the existing mummies of the members of royal families. A sample of 259 adult Egyptian mummies originating from various collections and published sources with body lengths (long bone measures or/and overall measurements, CT data) were analyzed, and royal mummies were scored with respect to the level of consanguinity. Male royals were taller than males in the general ancient Egyptian population, while female royals were shorter than females in the general population. The body height variation of the royals is significantly reduced when compared with a pool of non-royal mummies. This provides evidence for inbreeding resulting from consanguineous marriages. However, there appears to be no correlation between the level of inbreeding and individual body height. The random sample of general population does not show signs of inbreeding. Due to the present lack of larger, technically and ethically challenging genetic studies, the selected non-invasive approach of body height is the most reliable indicator of sibling marriages of pharaohs based on direct physical evidence.


Asunto(s)
Estatura/fisiología , Consanguinidad , Momias , Antropología Física , Antropometría , Antiguo Egipto , Femenino , Historia Antigua , Humanos , Masculino , Momias/diagnóstico por imagen , Momias/historia , Radiografía
15.
Skeletal Radiol ; 44(6): 811-21, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25662179

RESUMEN

OBJECTIVE: To study pathologies, peri- and postmortal alterations as well as the general preservation state of an ancient Iranian salt mummy. MATERIALS AND METHODS: Several mummified remains from two different time periods (1500-2500 BP) were found in the Chehrabad salt mine in Iran. Computed tomography was performed on Salt Man #4 (410-350 BC), the best preserved out of the six salt mummies (Siemens, Sensation 16; 512 × 512 matrix; 0.75-5 mm slice thickness, 240-mA tube current, 120-kV tube voltage, and 0.976-mm pixel size). RESULTS: Radiological analyses showed an excellent state of preservation of an adolescent body. Several normal variants such as aplasia of the frontal sinus as well as a rare congenital deformation of the 5th vertebral body (butterfly vertebra) have been observed. The individual shows multiple fractures, which is consistent with the theory that he died due to a collapse in the ancient salt mine. CONCLUSIONS: The salt preserved the soft tissue as well as parts of the inner organs remarkably well. However, further investigations including histology are needed to reveal additional details of the health status of this unique salt mummy.


Asunto(s)
Embalsamiento/historia , Fracturas Múltiples/diagnóstico por imagen , Fracturas Múltiples/historia , Momias/diagnóstico por imagen , Momias/historia , Adolescente , Autopsia , Historia Antigua , Humanos , Irán , Masculino , Radiografía
16.
Radiographics ; 33(1): 291-6, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23322842

RESUMEN

Ancient Egyptian and Peruvian mummies are extremely valuable historical remains, and noninvasive methods for their examination are desirable. The current standard of reference for radiologic imaging of mummies is computed tomography (CT), with tissue having a homogeneous appearance on all CT images. It was long believed that ancient mummified tissue could not be studied with magnetic resonance (MR) imaging because of the low water content in mummies. Recently, however, the usefulness of MR imaging in the evaluation of mummified tissue was demonstrated for the first time, with use of a special ultrashort echo time technique. The authors of the present study acquired and analyzed MR imaging and CT data from the left hands of two ancient Egyptian mummies and the head of a third Egyptian mummy (ca 1500-1100 bce), as well as data from an ancient Peruvian mummy (ca 1100 ce). CT was found to provide superior detail of the anatomic structures, mainly because of its higher spatial resolution. The signal intensity of mummified tissue varied greatly on MR images; thus, the quality of these images is not yet comparable to that of clinical MR images, and further research will be needed to determine the full capacity of MR imaging in this setting. Nevertheless, additional information may theoretically be obtained with MR imaging, which should be viewed as complementary to, rather than a replacement for, CT.


Asunto(s)
Imagen por Resonancia Magnética , Momias , Tomografía Computarizada por Rayos X , Egipto , Humanos , Perú
17.
Eur Spine J ; 20(5): 776-80, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-20632043

RESUMEN

Previous studies on the prevalence of spina bifida occulta have indicated a microevolutionary increase in its frequency and possible population differences in the prevalence of the condition. We studied the frequencies of closed and open sacral canals at each sacral level among two birth cohorts in Switzerland. Transverse CT scans and multiplanar reconstruction images of sacra of 95 males and 96 females born in 1940-1950 and 99 males and 94 females born in 1970-1980 in Switzerland were reviewed. We found that individuals born later have significantly more open sacral arches at all sacral levels compared to those born 30-40 years earlier. When results were related to previously published data on Australian cohorts, the trend was the same, but Swiss in both cohorts were less likely to have an open section than Australians at all locations apart from S2. This study confirmed a microevolutionary trend in the opening of sacral canal among two different generations in Switzerland and demonstrated a population difference in the prevalence of spina bifida occulta.


Asunto(s)
Sacro/anomalías , Espina Bífida Oculta/epidemiología , Adulto , Anciano , Antropometría/métodos , Evolución Biológica , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Radiografía , Sacro/diagnóstico por imagen , Espina Bífida Oculta/diagnóstico , Espina Bífida Oculta/diagnóstico por imagen , Canal Medular/anomalías , Canal Medular/diagnóstico por imagen , Suiza/epidemiología
18.
Am J Phys Anthropol ; 142(3): 497-500, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20544977

RESUMEN

Ancient mummified soft-tissues are a unique source to study the evolution of disease. Diagnostic imaging of such historic tissues is of foremost interest in paleoanthropology or paleopathology, with conventional x-ray and computed tomography (CT) being the gold-standard. Longer wavelength radiation in the far-infrared or Terahertz region allows diagnostic close-to-surface tissue differentiation of bone morphology while being harmless to human cells. The aim of this study is to show the feasibility and the morpho-diagnostic impact of THz imaging of historic remains. Images of an artificially embalmed ancient Egyptian human mummy hand, an artificially embalmed ancient Egyptian mummified fish and a macerated human lumbar vertebra were obtained by THz-pulse imaging and compared with conventional X-ray and CT images. Although conventional x-ray imaging provides higher spatial resolution, we found that THz-imaging is well-suited for the investigation of ancient mummified soft tissue and embalming-related substances / wrappings. In particular, bone and cartilaginous structures can be well differentiated from surrounding soft-tissues and bandage-wrappings by THz imaging. Furthermore, THz-pulse imaging also measures the time-delay of the pulsed signal when passing through the sample, which provides supplementary information on the optical density of the sample that is not obtained by X-ray and CT. Terahertz radiation provides a completely non-invasive diagnostic imaging modality for historic dry specimens. We anticipate this modality also to be used for detection of hidden objects in historic samples such as funerary amulets still in situ in wrapped mummies, as well as potentially for the identification of spectral signatures from chemical substances, e.g., in embalming essences.


Asunto(s)
Huesos/diagnóstico por imagen , Momias , Paleopatología/métodos , Imágen por Terahertz/métodos , Animales , Huesos/anatomía & histología , Peces , Mano/anatomía & histología , Mano/diagnóstico por imagen , Historia Antigua , Humanos , Columna Vertebral/anatomía & histología , Columna Vertebral/diagnóstico por imagen , Tomografía Computarizada por Rayos X
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