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Matson DM, Battezzati L, Galenko PK, Gandin CA, Gangopadhyay AK, Henein H, Kelton KF, Kolbe M, Valloton J, Vogel SC, Volkmann T. Electromagnetic levitation containerless processing of metallic materials in microgravity: rapid solidification. NPJ Microgravity 2023; 9:65. [PMID: 37582930 PMCID: PMC10427700 DOI: 10.1038/s41526-023-00310-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Accepted: 07/26/2023] [Indexed: 08/17/2023] Open
Abstract
Space levitation processing allows researchers to conduct benchmark tests in an effort to understand the physical phenomena involved in rapid solidification processing, including alloy thermodynamics, nucleation and growth, heat and mass transfer, solid/liquid interface dynamics, macro- and microstructural evolution, and defect formation. Supported by ground-based investigations, a major thrust is to develop and refine robust computational tools based on theoretical and applied approaches. This work is accomplished in conjunction with experiments designed for precise model validation with application to a broad range of industrial processes.
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Affiliation(s)
- D M Matson
- Department of Mechanical Engineering, Tufts University, Medford, MA, 02155, USA.
| | - L Battezzati
- Dipartimento di Chimica e Centro NIS, Università di Torino, Via P, Giuria 7, 10125, Torino, Italy
| | - P K Galenko
- Otto-Schott-Institut für Materialforschung, Friedrich Schiller Universität Jena, Jena, Germany
| | - Ch-A Gandin
- MINES Paris, PSL University, CEMEF UMR CNRS 7635, CS10207, 06904, Sophia Antipolis, France
| | - A K Gangopadhyay
- Department of Physics and the Institute of Materials Science & Engineering, Washington University, St. Louis, MO, 63130-4899, USA
| | - H Henein
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, AB, T6G 2G6, Canada
| | - K F Kelton
- Department of Physics and the Institute of Materials Science & Engineering, Washington University, St. Louis, MO, 63130-4899, USA
| | - M Kolbe
- Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt (DLR), 51170, Köln, Germany
| | - J Valloton
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, AB, T6G 2G6, Canada
| | - S C Vogel
- Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - T Volkmann
- Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt (DLR), 51170, Köln, Germany
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Sinha SK, Saxena A, Mishra V, Volkmann T, Kumar AMV, Nair SA, Moonan PK, Oeltmann JE, Chadha VK. Integration and decentralisation of TB-HIV services increases HIV testing of TB cases in Rajasthan, India. Public Health Action 2017; 7:71-73. [PMID: 28775947 DOI: 10.5588/pha.16.0060] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 12/31/2016] [Indexed: 11/10/2022] Open
Abstract
The proportion of tuberculosis (TB) patients tested for the human immunodeficiency virus (HIV) in the state of Ra-jasthan, India, is limited by the availability of HIV testing facilities. Rajasthan implemented a policy of initiating TB-HIV diagnosis at all health institutions in July 2013. The number of TB diagnostic facilities increased from 33 to 63 in Banswara District and from 22 to 68 in Jhunjhunu District, while the number of HIV testing facilities in these districts increased from 1 to 53 and from 10 to 81, respectively, after the policy implementation. The proportion of TB patients tested for HIV increased by respectively 27% and 19%.
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Affiliation(s)
- S K Sinha
- World Health Organization Country Office for India, New Delhi, India
| | - A Saxena
- State Tuberculosis Office, Directorate of Medical & Health Services, Jaipur, India
| | - V Mishra
- World Health Organization Country Office for India, New Delhi, India
| | - T Volkmann
- Division of Tuberculosis Elimination, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - A M V Kumar
- International Union Against Tuberculosis and Lung Disease, South-East Asia Office, New Delhi, India
| | - S A Nair
- World Health Organization Country Office for India, New Delhi, India
| | - P K Moonan
- Division of Tuberculosis Elimination, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - J E Oeltmann
- Division of Tuberculosis Elimination, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - V K Chadha
- Epidemiology and Research Division, National Tuberculosis Institute, Bangalore, India
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Volkmann T, Okelloh D, Agaya J, Cain K, Ooko B, Malika T, Burton D. Pilot implementation of a contact tracing intervention for tuberculosis case detection in Kisumu County, Kenya. Public Health Action 2016; 6:217-219. [PMID: 28123956 DOI: 10.5588/pha.16.0032] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Accepted: 08/30/2016] [Indexed: 11/10/2022] Open
Abstract
Leveraging an existing community health strategy, a contact tracing intervention was piloted under routine programmatic conditions at three facilities in Kisumu County, Kenya. Data collected during a 6-month period were compared to existing programmatic data. After implementation of the intervention, we found enhanced programmatic contact tracing practices, noting an increase in the proportions of index cases traced, symptomatic contacts referred, referred contacts presenting to a facility for tuberculosis screening, and eligible contacts started on isoniazid preventive therapy. As contact tracing is scaled up, health ministries should consider the adoption of similar contact tracing interventions to improve contact tracing practices.
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Affiliation(s)
- T Volkmann
- Division of Global HIV & Tuberculosis, Centers for Disease Control and Prevention (CDC), Atlanta, Georgia, USA
| | - D Okelloh
- Kenya Medical Research Institute, Kisumu County, Kenya
| | - J Agaya
- Kenya Medical Research Institute, Kisumu County, Kenya
| | - K Cain
- Division of Global HIV & Tuberculosis, Centers for Disease Control and Prevention (CDC), Atlanta, Georgia, USA
| | - B Ooko
- Division of Leprosy, Tuberculosis and Lung Diseases, Ministry of Health, Kisumu County, Kenya
| | - T Malika
- Division of Leprosy, Tuberculosis and Lung Diseases, Ministry of Health, Kisumu County, Kenya
| | - D Burton
- Division of TB Elimination, CDC, Atlanta, Georgia, USA
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Abstract
BACKGROUND Excess alcohol use among tuberculosis (TB) patients complicates TB control strategies. OBJECTIVES To characterize the role of excess alcohol use in TB control, we describe the epidemiology of excess alcohol use and TB in the United States among those aged ⩾15 years. DESIGN Using data reported to the National Tuberculosis Surveillance System, 1997-2012, we examined associations between excess alcohol use and TB treatment outcomes and markers for increased transmission (involvement in a local genotype cluster of cases) using multivariate logistic regression. We used Cox proportional hazards regression analysis to examine the relationship between excess alcohol use and the rate of conversion from positive to negative in sputum culture results. RESULTS Excess alcohol use was documented for 31 207 (15.1%) of 207 307 patients. Prevalence of excess alcohol use was greater among male patients (20.6%) and US-born patients (24.6%). Excess alcohol use was associated with a positive sputum smear result (aOR 1.23, 95%CI 1.18-1.28) and death during treatment (vs. completion of treatment) (aOR 1.16, 95%CI 1.10-1.22). The rate of culture conversion was higher among patients without excess alcohol use (adjusted hazard ratio 1.20, 95%CI 1.18-1.23). CONCLUSIONS Excess alcohol use was common among patients with TB, and was associated with TB transmission, lower rates of sputum culture conversion, and greater mortality.
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Affiliation(s)
- T Volkmann
- Epidemic Intelligence Service, assigned to Division of Tuberculosis Elimination, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - P K Moonan
- Division of Tuberculosis Elimination, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - R Miramontes
- Division of Tuberculosis Elimination, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - J E Oeltmann
- Division of Tuberculosis Elimination, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
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Rami A, Volkmann T, Agarwal R, Schoninger S, Nürnberger F, Saido TC, Winckler J. β2-Adrenergic receptor responsiveness of the calpain–calpastatin system and attenuation of neuronal death in rat hippocampus after transient global ischemia. Neurosci Res 2003; 47:373-82. [PMID: 14630341 DOI: 10.1016/j.neures.2003.07.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
In the CNS, where Ca(2+) overload has been established as a mechanism contributing to neuronal damage associated with excitotoxicity, stroke and ischemia, there is interest in understanding the role of calpain inhibition in rescuing neurons from death. In these settings, the activation of large stores of latent calpain may rapidly lead to the demise of the neuron within hours. The activity of calpain is strictly regulated by calcium concentrations and interactions with calpastatin (endogenous calpain inhibitor). The interaction between calpains and calpastatin is calcium dependent, and little is known about the regulation of the neuronal calpain-calpastatin system in vivo. It has been postulated that calpastatin can be modulated by nerve growth factors (NGFs). We have demonstrated in vitro as well as in vivo a neuroprotective effect of the beta(2)-adrenoceptor agonist clenbuterol (CLN) mediated through an increased NGF expression. In this study we attempt to find out whether CLN is capable (1) of modulating proteolysis regulated by the calpain-calpastatin system and (2) of attenuating DNA-fragmentation induced by cerebral ischemia. Rats received CLN daily for 1 week, were then subjected to ischemia and finally perfused at different times post-ischemia. The proteolytic activity of calpain was measured by the immunolocalisation of calpastatin and spectrin-breakdown products (SBP). The time course of apoptosis was assessed by terminal dUTP nick end-labeling (TUNEL)-staining. CLN reduced CA1-hippocampal cell damage by 23%, attenuated DNA-laddering and decreased proteolysis of spectrin by enhancing calpastatin activity. These results provide evidence that CLN is a potent neuroprotective substance, which through the enhancement of calpastatin synthesis attenuates the apoptotic machinery and modulates proteolysis.
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Affiliation(s)
- A Rami
- Anatomisches Institut III, Dr. Senckenbergische Anatomie, Klinikum der JWG-Universität, Theodor-Stern-Kai 7, 60590 Frankfurt/Main, Germany.
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Rami A, Volkmann T, Winckler J. Effective reduction of neuronal death by inhibiting gap junctional intercellular communication in a rodent model of global transient cerebral ischemia. Exp Neurol 2001; 170:297-304. [PMID: 11476596 DOI: 10.1006/exnr.2001.7712] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Gap junctions assemble astrocytes into syncytia, allowing exchange of metabolites, catabolites, and second-messenger molecules. Connexin43 is the predominant connexin of astrocytic gap junctions. The distribution of gap junction protein connexin43 was analyzed in different subfields of the hippocampal formation as a function of time after transient forebrain ischemia. One decisive key step in understanding why an ischemic insult gradually expands may be to establish how gap junction channels permit dying cells in the ischemic focus to communicate, in particular, with viable cells. The role of gap junctional intercellular communication in the hippocampus under ischemic conditions could be decisive for cell death propagation. We found that the vulnerable CA1/CA2 subfields have a higher density of gap junctions than the resistant CA3/CA4 areas, that changes in the distribution of connexin43 immunoreactivity may correlate with the phenomenon of selective vulnerability, and that inhibition of astrocytic gap junction permeability by octanol restricts the flow of undesirable neurotoxins that could potentially exacerbate neuronal damage. This provides a novel perspective for analysis of the pathophysiology of cerebral ischemia.
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Affiliation(s)
- A Rami
- Anatomisches Institut III, Dr. Senckenbergische Anatomie, Universitätsklinikum, Theodor-Stern-Kai 7, Frankfurt, 60590, FRG.
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Herlach DM, Gillessen F, Volkmann T, Wollgarten M, Urban K. Phase selection in undercooled quasicrystal-forming Al-Mn alloy melts. Phys Rev B Condens Matter 1992; 46:5203-5210. [PMID: 10004295 DOI: 10.1103/physrevb.46.5203] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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