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  1. Thesis ; Online: Alkalisch aktivierte Systeme auf Basis von Hüttensandmehlen

    Tänzer, Ricarda

    Untersuchung des Einflusses der Hüttensandzusammensetzung auf die Bindemitteleigenschaften und Verhalten alkalisch aktivierter Mörtel hinsichtlich einer Alkali-Kieselsäure-Reaktion

    2018  

    Abstract: ... des Wasserglasmoduls (molares Verhältnis SiO2/M2O, M = Li, Na, K), der Alkalikonzentration und des Alkaliions (Li, Na ... Alkalisensitivität über mehrere Monate bei 40 °C in der Nebelkammer beobachtet. Als Fazit ist festzuhalten ...

    Abstract Alternative Bindemittel besitzen ökonomische und ökologische Vorteile sowie eine Vielzahl an positiven Eigenschaften (hoher Widerstand gegen aggressive Medien, hohe Druckfestigkeit, hoher Frostwiderstand, geringe beziehungsweise schnelle Abgabe von Reaktionswärme, geringe Porosität oder hohe Temperaturbeständigkeit). Die Eigenschaften hängen aber maßgeblich von der Art des Bindemitteltyps ab. Für alkalisch aktivierte Hüttensandmehle sind hier die chemisch-mineralogische Zusammensetzung des Hüttensandes sowie die Art und Dosierung des Anregers von entscheidender Bedeutung. Erstes Ziel dieser Arbeit war es daher den Einfluss verschiedener Hüttensandparameter, insbesondere der chemischen Zusammensetzung (CaO/SiO2-Verhältnis, TiO2-Gehalt, Al2O3-Gehalt, MgO-Gehalt) sowie der Schmelztemperatur und mineralogischen Zusammensetzung (Glasgehalt), auf den Reaktionsverlauf, die Festigkeit und die Phasenneubildung bei Anregung mit ausgewählten alkalischen Aktivatoren zu untersuchen. Im Ergebnis konnten die einzelnen Hüttensandcharakteristika in 4 Kategorien eingeteilt werden. Die Schmelztemperatur und der TiO2-Gehalt besitzen keinen Einfluss auf das Abbindeverhalten und die Reaktionsprodukte, während der des Glasgehaltes und der des MgO-Gehaltes gering ist. Ein erhöhter Al2O3-Gehalt wirkt sich stärker aus und zeigt eine Abhängigkeit vom gewählten Anreger. Den größten Einfluss, unabhängig vom Aktivator, besitzt jedoch das CaO/SiO2-Verhältnis des Hüttensandes. Für eine wirtschaftliche Nutzung alkalisch aktivierter Hüttensandmehle zum Beispiel für Beton-anwendungen sind auch deren Dauerhaftigkeitseigenschaften von Bedeutung. Da Mörtel und Betone mit alkalisch aktivierten Hüttensandmehlen als Bindemittel im Vergleich zu portland-zementgebundenen Systemen eine um das 10-fache erhöhte Menge Alkalien enthalten, stellt sich die Frage, ob ein erhöhtes Risiko für eine Alkali-Kieselsäure-Reaktion (AKR) bei diesen Systemen besteht. Zweites Ziel dieser Arbeit war es in einem Modellsystem den Einfluss des alkalischen Anregers, vornehmlich Alkalisilicat, hinsichtlich des Wasserglasmoduls (molares Verhältnis SiO2/M2O, M = Li, Na, K), der Alkalikonzentration und des Alkaliions (Li, Na, K) auf eine Alkali-Kieselsäure-Reaktion zu untersuchen. Hierfür wurden Mörtel aus einem industriellen Hüttensandmehl, verschiedenen Anregern, sowie einer Borosilicatglaskörnung mit definierter Alkalisensitivität über mehrere Monate bei 40 °C in der Nebelkammer beobachtet. Als Fazit ist festzuhalten, dass der Wasserglasmodul einen erheblichen Einfluss auf das Schwinden innerhalb der ersten 7 d und das spätere Quellen hat und die Wirkung des Alkaliions (Natrium und Kalium) sowie der Alkalikonzentration beeinflusst.
    Keywords Chemical engineering
    Subject code 660
    Language GER
    Publishing date 2018-01-01 00:00:01.0
    Publisher Technische Universitaet Berlin (Germany)
    Publishing country us
    Document type Thesis ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  2. Article: An interview with Radford C, Tanzer, M.D. conducted by William D. Morain, M.D.

    Tanzer, R C

    Annals of plastic surgery

    1983  Volume 10, Issue 1, Page(s) 72–85

    MeSH term(s) Adolescent ; Ear, External/abnormalities ; Ear, External/surgery ; Humans ; Male ; Surgery, Plastic/methods
    Language English
    Publishing date 1983-01
    Publishing country United States
    Document type Journal Article
    ZDB-ID 423835-7
    ISSN 1536-3708 ; 0148-7043
    ISSN (online) 1536-3708
    ISSN 0148-7043
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Augmented Reality in Arthroplasty: An Overview of Clinical Applications, Benefits, and Limitations.

    Tanzer, Michael / Laverdière, Carl / Barimani, Bardia / Hart, Adam

    The Journal of the American Academy of Orthopaedic Surgeons

    2022  Volume 30, Issue 10, Page(s) e760–e768

    Abstract: Augmented reality (AR) is a natural extension of computer-assisted surgery whereby a computer-generated image is superimposed on the surgeon's field of vision to assist in the planning and execution of the procedure. This emerging technology shows great ... ...

    Abstract Augmented reality (AR) is a natural extension of computer-assisted surgery whereby a computer-generated image is superimposed on the surgeon's field of vision to assist in the planning and execution of the procedure. This emerging technology shows great potential in the field of arthroplasty, improving efficiency, limb alignment, and implant position. AR has shown the capacity to build on computer navigation systems while providing more elaborate information in a streamlined workflow to the user. This review investigates the current uses of AR in the field of arthroplasty and discusses outcomes, limitations, and potential future directions.
    MeSH term(s) Arthroplasty ; Augmented Reality ; Humans ; Surgery, Computer-Assisted/methods
    Language English
    Publishing date 2022-03-02
    Publishing country United States
    Document type Journal Article ; Review
    ZDB-ID 1200524-1
    ISSN 1940-5480 ; 1067-151X
    ISSN (online) 1940-5480
    ISSN 1067-151X
    DOI 10.5435/JAAOS-D-21-00964
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Psychological interventions for interoception in mental health disorders: A systematic review of randomized-controlled trials.

    Heim, Nikolas / Bobou, Marina / Tanzer, Michal / Jenkinson, Paul M / Steinert, Christiane / Fotopoulou, Aikaterini

    Psychiatry and clinical neurosciences

    2023  Volume 77, Issue 10, Page(s) 530–540

    Abstract: Disturbed interoception (i.e., the sensing, awareness, and regulation of internal body signals) has been found across several mental disorders, leading to the development of interoception-based interventions (IBIs). Searching PubMed and PsycINFO, we ... ...

    Abstract Disturbed interoception (i.e., the sensing, awareness, and regulation of internal body signals) has been found across several mental disorders, leading to the development of interoception-based interventions (IBIs). Searching PubMed and PsycINFO, we conducted the first systematic review of randomized-controlled trials (RCTs) investigating the efficacy of behavioral IBIs at improving interoception and target symptoms of mental disorders in comparison to a non-interoception-based control condition [CRD42021297993]. Thirty-one RCTs fulfilled inclusion criteria. Across all studies, a pattern emerged with 20 (64.5%) RCTs demonstrating IBIs to be more efficacious at improving interoception compared to control conditions. The most promising results were found for post-traumatic stress disorder, irritable bowel syndrome, fibromyalgia and substance use disorders. Regarding symptom improvement, the evidence was inconclusive. The IBIs were heterogenous in their approach to improving interoception. The quality of RCTs was moderate to good. In conclusion, IBIs are potentially efficacious at improving interoception for some mental disorders. In terms of symptom reduction, the evidence is less promising. Future research on the efficacy of IBIs is needed.
    MeSH term(s) Humans ; Mental Health ; Psychosocial Intervention ; Interoception ; Stress Disorders, Post-Traumatic/psychology ; Substance-Related Disorders ; Randomized Controlled Trials as Topic
    Language English
    Publishing date 2023-08-09
    Publishing country Australia
    Document type Systematic Review ; Journal Article ; Review
    ZDB-ID 1292906-2
    ISSN 1440-1819 ; 1323-1316
    ISSN (online) 1440-1819
    ISSN 1323-1316
    DOI 10.1111/pcn.13576
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: A novel method for quantification of cefazolin local tissue concentration in blood, fat, synovium, and bone marrow using liquid chromatography - mass spectrometry.

    Russo, M / Monnin, C / Zhang, Y L / Montreuil, J / Tanzer, M / Avizonis, D / Hart, A

    Journal of pharmaceutical and biomedical analysis

    2023  Volume 234, Page(s) 115566

    Abstract: To be effective, the concentration of antibiotic used must exceed the minimum inhibitory concentration (MIC) against infecting organisms at and in the surgical site. Few studies follow antibiotic levels for tissues that are manipulated during surgery. ... ...

    Abstract To be effective, the concentration of antibiotic used must exceed the minimum inhibitory concentration (MIC) against infecting organisms at and in the surgical site. Few studies follow antibiotic levels for tissues that are manipulated during surgery. The aim of this work was to develop and validate a novel LC-MS method as well as an efficient extraction technique for the quantification of cefazolin in local tissues and whole blood. This method uses the same efficient extraction method across multiple tissue types affected by orthopedic surgery: blood, fat, synovium, and bone marrow. The ability to quantify cefazolin in these tissues will help identify surgical techniques and antibiotic dosing protocols that better protect patients from infection. The internal standard,
    MeSH term(s) Humans ; Cefazolin ; Bone Marrow ; Reproducibility of Results ; Surgical Wound Infection/drug therapy ; Antibiotic Prophylaxis/methods ; Anti-Bacterial Agents ; Chromatography, Liquid ; Mass Spectrometry
    Chemical Substances Cefazolin (IHS69L0Y4T) ; Anti-Bacterial Agents
    Language English
    Publishing date 2023-07-06
    Publishing country England
    Document type Journal Article
    ZDB-ID 604917-5
    ISSN 1873-264X ; 0731-7085
    ISSN (online) 1873-264X
    ISSN 0731-7085
    DOI 10.1016/j.jpba.2023.115566
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Capsular closure outweighs head size in preventing dislocation following revision total hip arthroplasty.

    Pedneault, Christopher / Tanzer, Dylan / Nooh, Anas / Smith, Karen / Tanzer, Michael

    Hip international : the journal of clinical and experimental research on hip pathology and therapy

    2019  Volume 30, Issue 2, Page(s) 141–146

    Abstract: Introduction: The high dislocation rate following revision total hip arthroplasty (THA) has been shown to be significantly reduced by closing the posterior capsule and by the use of large diameter femoral heads. The relative importance of each of these ... ...

    Abstract Introduction: The high dislocation rate following revision total hip arthroplasty (THA) has been shown to be significantly reduced by closing the posterior capsule and by the use of large diameter femoral heads. The relative importance of each of these strategies on the rate of dislocation remains unknown. We undertook a study to determine if increasing femoral head diameter, in addition to posterior capsular closure would influence the dislocation rate following revision THA.
    Methods: We retrospectively reviewed 144 patients who underwent a revision THA. We included all patients who underwent revision THA with closure of the posterior capsule and who had at least a 2-year minimum follow-up. 48 patients had a 28-mm femoral head, 47 had a 32-mm head and 49 patients had a 36-mm femoral head.
    Results: At a minimum follow-up of 2 years, there were 3 dislocations. There were no dislocations in the 28-mm group (0%), 2 in the 32-mm group (4%) and 1 in the 36-mm group (2%). Head size alone was not found to significantly decrease the risk of dislocation (28-mm versus 32-mm
    Conclusion: Both large diameter heads and careful attention to surgical technique with posterior capsular closure can decrease the historically high dislocation rate after revision THA when utilising the posterolateral approach. Capsular closure outweighs the effect of femoral head diameter in preventing dislocation following revision THA through a posterolateral approach.
    MeSH term(s) Adult ; Aged ; Aged, 80 and over ; Arthroplasty, Replacement, Hip/adverse effects ; Female ; Femur Head/surgery ; Hip Dislocation/prevention & control ; Hip Prosthesis ; Humans ; Joint Capsule/surgery ; Male ; Middle Aged ; Prosthesis Design ; Reoperation ; Retrospective Studies
    Language English
    Publishing date 2019-05-10
    Publishing country United States
    Document type Journal Article
    ZDB-ID 1162513-2
    ISSN 1724-6067 ; 1120-7000
    ISSN (online) 1724-6067
    ISSN 1120-7000
    DOI 10.1177/1120700019848107
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article: Time-resolved RNA signatures of CD4+ T cells in Parkinson's disease.

    Diener, Caroline / Hart, Martin / Kehl, Tim / Becker-Dorison, Anouck / Tänzer, Tanja / Schub, David / Krammes, Lena / Sester, Martina / Keller, Andreas / Unger, Marcus / Walch-Rückheim, Barbara / Lenhof, Hans-Peter / Meese, Eckart

    Cell death discovery

    2023  Volume 9, Issue 1, Page(s) 18

    Abstract: Parkinson's disease (PD) emerges as a complex, multifactorial disease. While there is increasing evidence that dysregulated T cells play a central role in PD pathogenesis, elucidation of the pathomechanical changes in related signaling is still in its ... ...

    Abstract Parkinson's disease (PD) emerges as a complex, multifactorial disease. While there is increasing evidence that dysregulated T cells play a central role in PD pathogenesis, elucidation of the pathomechanical changes in related signaling is still in its beginnings. We employed time-resolved RNA expression upon the activation of peripheral CD4+ T cells to track and functionally relate changes on cellular signaling in representative cases of patients at different stages of PD. While only few miRNAs showed time-course related expression changes in PD, we identified groups of genes with significantly altered expression for each different time window. Towards a further understanding of the functional consequences, we highlighted pathways with decreased or increased activity in PD, including the most prominent altered IL-17 pathway. Flow cytometric analyses showed not only an increased prevalence of Th17 cells but also a specific subtype of IL-17 producing γδ-T cells, indicating a previously unknown role in PD pathogenesis.
    Language English
    Publishing date 2023-01-21
    Publishing country United States
    Document type Journal Article
    ISSN 2058-7716
    ISSN 2058-7716
    DOI 10.1038/s41420-023-01333-0
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article: Marital Relationship and Quality of Life in Couples Following Hip Replacement Surgery.

    Tanzer, Michael / Pedneault, Christopher / Yakobov, Esther / Hart, Adam / Sullivan, Michael

    Life (Basel, Switzerland)

    2021  Volume 11, Issue 5

    Abstract: For the majority of patients with osteoarthritis, total hip (THA) arthroplasty results in a significant reduction in pain, emotional distress, and disability and a significant improvement in their quality of life. Little is known about how these recovery- ...

    Abstract For the majority of patients with osteoarthritis, total hip (THA) arthroplasty results in a significant reduction in pain, emotional distress, and disability and a significant improvement in their quality of life. Little is known about how these recovery-related changes impact the spouse or the marital relationship.
    Methods: Twenty-nine couples whose spouse underwent a THA (29 THA) participated in a semi-structured retrospective interview designed for this study. They were each asked to recall the level of pain before and after surgery and to provide a numerical rating score for questions pertaining to the level of disability in seven different activities of daily living. Couples were also asked to list in order of importance the five ways in which the surgery affected their overall quality of life.
    Results: The spouses estimated their partner's pain, both pre- and postoperatively, to be significantly higher level than the patient's perception. The spouses perceived a greater improvement in family/home responsibilities, recreation and social activities, and in their occupation than that noted by the partner. After the arthroplasty, the spouses indicated that their lives had improved with respect to doing more activities/leisure (72%), because their partner had less suffering (59%), they had more independence/less caregiving (55%), it improved their marital relationship (52%), they had a better social/family life (28%), and they were able to travel (28%).
    Conclusions: This study indicates that THA result in a significant improvement in quality of life not only for the patients, but also for their spouses.
    Language English
    Publishing date 2021-04-28
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2662250-6
    ISSN 2075-1729
    ISSN 2075-1729
    DOI 10.3390/life11050401
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article: Reliability of Time Domain AS-OCT in Measuring the Extraocular Rectus Muscle Insertion-Limbus Distances: A Systematic Review and Meta-Analysis.

    Kim, Eric J / Ganga, Arjun / Rana, Viren K / Tanzer, Joshua R / Ronquillo, Yasmyne C / Moshirfar, Majid

    Clinical ophthalmology (Auckland, N.Z.)

    2022  Volume 16, Page(s) 2823–2835

    Abstract: Purpose: The insertion-limbus distances of the extraocular muscles are clinically relevant in the preoperative planning of strabismus surgeries, especially in reoperations when information regarding insertion sites is not accessible to the surgeon. In ... ...

    Abstract Purpose: The insertion-limbus distances of the extraocular muscles are clinically relevant in the preoperative planning of strabismus surgeries, especially in reoperations when information regarding insertion sites is not accessible to the surgeon. In this systematic review, we assess the reliability of time-domain anterior segment optical coherence tomography (TD AS-OCT) in determining insertion-limbus distances preoperatively by investigating prior studies that compare preoperative TD AS-OCT measurements of the insertion-limbus distances to those of calipers, which are assumed to be the gold standard.
    Methods: Systematically reviewing EMBASE, PubMed, Google Scholar, Science Direct, and Web of Science, 2 members screened for studies that compared preoperative TD AS-OCT measurements to those of intraoperative calipers, the gold standard. To assess the risk of bias for individual studies, the reviewers utilized the ROBINS-I tool, a Cochrane's collaboration tool used to assess bias in studies that are not randomized. For the meta-analysis, parallel forms reliability was examined and estimated as the Pearson product-moment correlation between TD AS-OCT measurements and surgical caliper measurements.
    Results: Six out of the seven eligible studies provided measures of reliability that were >0.7. These six records were eligible for meta-analysis. There was no evidence of a difference between means of TD AS-OCT and caliper measurements ( = 6.81, 95% CI [6.41, 7.22]; = 6.73, 95% CI [6.18, 7.29]; = 0.08, 95% CI [-0.44, 0.61]). Reliability was estimated to be good ( = 0.91) though the lower limit was slightly below the recommended minimum acceptable level of 0.70 (95% CI [0.65, >0.99]).
    Conclusion: In the setting of primary surgeries, TD AS-OCT has an acceptable reliability. However, there is insufficient data to conclude whether TD AS-OCT has an acceptable reliability in the setting of reoperations.
    Language English
    Publishing date 2022-08-25
    Publishing country New Zealand
    Document type Journal Article ; Review
    ISSN 1177-5467
    ISSN 1177-5467
    DOI 10.2147/OPTH.S381644
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: P055 Sociodemographic Differences in Fecal Enteropathogen Testing Patterns in Adults Hospitalized for Inflammatory Bowel Disease Flares.

    Tse, Chung Sang / Andrea, Sarah / Elfanagely, Yousef / Tanzer, Joshua / Rupawala, Abbas

    The American journal of gastroenterology

    2022  Volume 116, Issue Suppl 1, Page(s) S14

    Abstract: ... Enteropathogen testing (may be >1) was obtained in 46% of hospitalizations: 42% tested for C. difficile; 23 ... parasites). 10% of the tests were positive, most commonly for C. difficile (5%), E. coli spp (0.6 ... observed (female 45%, male 46%, F:M, RR 1.01, 95% CI 0.90,1.15), Hispanic patients were more likely ...

    Abstract Background: Adults with inflammatory bowel disease (IBD) have increased risks for gastrointestinal infections. Single-center studies in Michigan and New York report 17-31% positive enteropathogen tests in patients with symptomatic IBD. Population-based studies are lacking, particularly on factors that determine who undergo testing. Health inequities may exist in the care of patients with IBD where certain groups systematically experience social and/or economic disparities. We aim to assess sociodemographic and healthcare factors associated with enteropathogen testing of hospitalized IBD patients.
    Methods: In this retrospective cohort study, we identified 770 patients with IBD who had 1,189 hospital admissions for primary symptoms consistent with IBD flares/enteric infections at 3 hospitals (tertiary referral teaching, community, and county) in the largest healthcare system in Rhode Island from January 2017-March 2019. Using modified Poisson regression to estimate relative risks (RR) and 95% Confidence Intervals (CIs), we assessed enteropathogen testing status as a function of sociodemographic and clinical characteristics in separate models.
    Results: Patients with IBD hospitalized with symptoms consistent with IBD flares or enteric infections disproportionately had Crohn's disease (69% vs. 31% UC). Patients were 47 years old on average, 60% women, 79% non-Hispanic white, 13% Hispanic, and 7% non-Hispanic Black. Over half (55%) were privately insured, 42% publicly insured, and 2% uninsured. Over half (55%) of patients were treated with glucocorticoids within 1 week of hospitalization while 35% were on biologics. The top 5 primary symptoms for hospitalization were abdominal pain (63%), GI bleeding (8%), fever (8%), vomiting (7%), and diarrhea (7%). Enteropathogen testing (may be >1) was obtained in 46% of hospitalizations: 42% tested for C. difficile; 23 % tested for Salmonella spp., Shigella spp./enteroinvasive E. coli, Campylobacter spp., and Shiga toxin-producing organisms; and 15% had extensive testing for 22 enteropathogens (13 bacteria, 5 viruses, and 4 parasites). 10% of the tests were positive, most commonly for C. difficile (5%), E. coli spp (0.6%), Campylobacter spp (0.5%), Salmonella (0.3%), and Norovirus (0.3%). While gender differences in testing were not observed (female 45%, male 46%, F:M, RR 1.01, 95% CI 0.90,1.15), Hispanic patients were more likely to undergo enteropathogen testing than non-Hispanic white patients (58% vs 44%; RR 1.21, 95% CI 1.02-1.43). Relative to patients hospitalized at the tertiary referral teaching hospital, patients at the county hospital were 29% less likely (95% CI, 0.54-0.93) and those at the community hospital were 22% (95% CI 0.78-1.01) less likely to have enteropathogen testing. Enteropathogen testing occurred most frequently among the privately insured 48%, while uninsured were comparatively 20% less likely and publicly insured were 10% less likely to undergo testing, though neither comparison was statistically significant.
    Conclusion: Racial/ethnic (Hispanic vs non-Hispanic White) and healthcare settings (county vs tertiary referral teaching hospital) differences in enteropathogen testing patterns were observed in adults with IBD hospitalized primarily for GI symptoms at the state of Rhode Island's largest healthcare system. Further studies to assess health inequities, including sociodemographic and organizational differences, in the healthcare delivery in IBD are warranted.
    Language English
    Publishing date 2022-08-12
    Publishing country United States
    Document type Journal Article
    ZDB-ID 390122-1
    ISSN 1572-0241 ; 0002-9270
    ISSN (online) 1572-0241
    ISSN 0002-9270
    DOI 10.14309/01.ajg.0000798820.49929.ce
    Database MEDical Literature Analysis and Retrieval System OnLINE

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