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Von Seggern J, Klotz S, Cantow HJ. Reptation and constraint release in linear polymer melts: an experimental study. Macromolecules 2002. [DOI: 10.1021/ma00011a039] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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127
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Prinzing A, Durka W, Klotz S, Brandl R. The niche of higher plants: evidence for phylogenetic conservatism. Proc Biol Sci 2001; 268:2383-9. [PMID: 11703879 PMCID: PMC1088890 DOI: 10.1098/rspb.2001.1801] [Citation(s) in RCA: 349] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
A species' ecological niche depends on the species' adaptations to its present habitat, but also on the legacy from its ancestors. Most authors argue that such a phylogenetic niche conservatism is of minor importance, although no quantitative analyses across a major taxon is available. Higher plants from central Europe offer a unique opportunity for such an exercise, as the niche positions along various environmental gradients are available for most species. We quantified niche conservatism by two approaches. First, we used a phylogenetic tree and quantified the degree of retention of niches across the tree. Depending on the gradient, the values ranged from 0.43 to 0.22. This was significantly greater than the null expectation. Second, we used a taxonomy and quantified the amount of variance among species that could be explained at higher taxonomic levels. The values ranged from 25 to 72%. Again, this was significantly higher than the null expectation. Thus, both approaches indicated a clear niche conservatism. The distribution of conservatism across taxonomic levels differed considerably among environmental gradients. The differences among environmental gradients could be correlated with the palaeoenvironmental conditions during the radiation of the phylogenetic lineages. Thus, niche conservatism among extant plant species may reflect the opportunities of their ancestors during their diversification.
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128
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Klotz S, Vestring T, Rötker J, Schmidt C, Scheld HH, Schmid C. Diagnosis and treatment of nonocclusive mesenteric ischemia after open heart surgery. Ann Thorac Surg 2001; 72:1583-6. [PMID: 11722048 DOI: 10.1016/s0003-4975(01)03179-4] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
BACKGROUND Acute nonocclusive mesenteric ischemia (NOMI) is a rare but often fatal event after cardiac surgery. METHODS Twenty patients with ongoing ileus after cardiac surgery despite maximal laxative treatment underwent selective mesenteric angiography. In cases of pathological radiographic findings, papaverine was continuously administered via an intraarterial perfusion catheter. RESULTS Severe NOMI was confirmed in seven patients (mean lactate: 6.9 +/- 8.3 mg/dL), mild to moderate findings in another seven (mean lactate: 1.4 +/- 1.1 mg/dL). One patient had thromboembolic occlusion of the superior mesenteric artery; five patients demonstrated normal imaging findings. In nine of fourteen patients (64%) treated with papaverine, symptoms improved within hours (defecation occurred after 4-29 hours, mean 13 +/- 8.1 hours). No side effects or complications occurred in connection with the papaverine treatment. The clinical condition of five patients deteriorated. Four patients underwent laparotomy with creation of an ileostomy or colostomy, two of whom presented with severe intestinal ischemia and later died. One patient died prior to laparotomy. CONCLUSIONS Selective mesenteric angiography with continuous papaverine administration is a simple, fast, and effective diagnostic and therapeutic tool to reduce the need for laparotomy for symptoms of ileus after open-heart surgery.
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Klotz S, Hammel D, Schmidt C, Scheld HH. False aneurysm of ascending aorta-anastomosis after orthotopic heart transplantation. Eur J Cardiothorac Surg 2001; 20:847. [PMID: 11574236 DOI: 10.1016/s1010-7940(01)00891-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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130
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Klotz S, Braden M. Phonon dispersion of bcc iron to 10 GPa. PHYSICAL REVIEW LETTERS 2000; 85:3209-3212. [PMID: 11019303 DOI: 10.1103/physrevlett.85.3209] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2000] [Indexed: 05/23/2023]
Abstract
The phonon dispersion of bcc iron under high pressure to 10 GPa was measured at 300 K by inelastic neutron scattering. Its pressure dependence is surprisingly uniform. Contrary to the behavior found in other bcc elements, there is a lack of any significant pretransitional behavior close to the martensitic bcc-hcp transition which could be related to the Burgers mechanism. This finding confirms predictions by spin-polarized total energy calculations that explain the transition by the effect of pressure on the magnetism of iron. The high pressure frequencies were used to develop a lattice dynamical model from which thermodynamic quantities can be determined at any pressure to 10 GPa.
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131
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Grima Gallardo P, Besson J, Iti� J, Gauthier M, M�zouar M, Klotz S, H�usermann D, Hanfland M. Uniaxial Stress Component in WC Toroidal Anvils under High Pressure and Temperature. ACTA ACUST UNITED AC 2000. [DOI: 10.1002/1521-396x(200008)180:2<427::aid-pssa427>3.0.co;2-l] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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132
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Loveday JS, Nelmes RJ, Klotz S, Besson JM, Hamel G. Pressure-induced hydrogen bonding: structure of D2S phase I'. PHYSICAL REVIEW LETTERS 2000; 85:1024-1027. [PMID: 10991465 DOI: 10.1103/physrevlett.85.1024] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2000] [Indexed: 05/23/2023]
Abstract
The full structure of the high-pressure cubic phase I' of hydrogen sulfide has been solved using neutron diffraction data. The molecules are partially rotationally disordered about the <111> axes, as in phase II at ambient pressure but with markedly greater nonuniformity of the toroidal D distribution. The changes in structure at the II-->I' transition signal the onset of significant pressure-induced hydrogen bonding.
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Klotz S, Besson JM, Hamel G, Nelmes RJ, Loveday JS, Marshall WG. Metastable ice VII at low temperature and ambient pressure. Nature 1999. [DOI: 10.1038/19480] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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134
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Wiltfang J, Klotz S, Wiltfang J, Jordan W, Cohrs S, Engelbe W, Hajak G. First results on daytime submandibular electrostimulation of suprahyoidal muscles to prevent night-time hypopharyngeal collapse in obstructive sleep apnea syndrome. Int J Oral Maxillofac Surg 1999. [DOI: 10.1016/s0901-5027(99)80670-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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135
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Wiltfang J, Klotz S, Wiltfang J, Jordan W, Cohrs S, Engelbe W, Hajak G. First results on daytime submandibular electrostimulation of suprahyoidal muscles to prevent night-time hypopharyngeal collapse in obstructive sleep apnea syndrome. Int J Oral Maxillofac Surg 1999; 28:21-5. [PMID: 10065643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Daytime submandibular electrostimulation (dSE) of suprahyoidal muscles was applied to prevent sleep-associated collapse of the tongue into the hypopharyngeal airway. By placing the stimulatory electrodes intra- and extraorally, recruitment of stimulated muscle fibers at low current densities was improved. The significant impact of electrostimulation on suprahyoidal muscle force was initially demonstrated in healthy controls as compared to placebo-treated volunteers. The morphology of suprahyoidal muscles was not affected by this treatment. A patient with obstructive sleep apnea syndrome initially presented with a respiratory disturbance index (RDI) of 13.2, an oxygen desaturation index of 23 and a minimal oxygen saturation of 75%. After two weeks of placebo treatment (TENS-stimulation), respiratory parameters remained unchanged. Two weeks of dSE treatment, however, improved the RDI to 3.9, the oxygen desaturation index from 23 to 2.8 and the minimal oxygen saturation from 75% to 88%. 3D-sonography showed considerable hypertrophy of the stimulated muscles. These results indicate that dSE may prevent episodes of apnea induced by sleep-associated hypopharyngeal collapse of the tongue.
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Wiltfang J, Klotz S, Wiltfang J, Jordan W, Cohrs S, Engelbe W, Hajak G. First results on daytime submandibular electrostimulation of suprahyoidal muscles to prevent night-time hypopharyngeal collapse in obstructive sleep apnea syndrome. Int J Oral Maxillofac Surg 1999. [DOI: 10.1034/j.1399-0020.1999.280105.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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137
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Urbach H, Brechtelsbauer D, Klotz S, Bendszus M, Solymosi L. [Detectability of new medial infarcts by CT: appearance of ischemic signs]. ROFO-FORTSCHR RONTG 1997; 166:502-6. [PMID: 9273002 DOI: 10.1055/s-2007-1015467] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
PURPOSE To evaluate the detectability of acute middle cerebral artery (MCA) infarctions by CT with regard to the time interval after symptom onset and to the infarction size. Analysis of the chronological appearance of signs of ischaemia. MATERIAL AND METHODS Two examiners retrospectively and independently evaluated CT scans from 171 patients with acute MCA infarctions performed within 24 hours after onset of symptoms. RESULTS 92, respectively 87% of the Infarctions were correctly diagnosed. The detection rate did not increase after the first hour after onset of symptoms. All MCA infarctions involving the lentiform nucleus, but only 83% of the infarctions covering < 33% of the MCA area, were recognised. The hyperdense middle cerebral artery sign (HMCA5) was present in 75% of the infarctions in the first 90 minutes and in 15% from hour 12 to 24. Hypodensity of the lentiform nucleus appeared within 150 minutes, hypodensity of the convexity cortex at the earliest 60 minutes after onset of symptoms. CONCLUSIONS The detection rate of acute MCA infarctions corresponds with the infarction size, but does not significantly change after the first hour after symptom onset.
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Wagner J, Klotz S, Haufe CC, Danser JA, Amann K, Ganten D, Ritz E. Progression of renal failure after subtotal nephrectomy in transgenic rats carrying an additional renin gene [TGR(mREN2)27]. J Hypertens 1997; 15:441-9. [PMID: 9211179 DOI: 10.1097/00004872-199715040-00015] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE To study the evolution of glomerulosclerosis after renal ablation in a model with abnormal regulation of the renin gene. METHODS Four-month-old female ovariectomized hypertensive heterozygous transgenic rats (TGR) harbouring the murine REN-2 gene were compared with pressure-matched, pair-fed, stroke-prone, spontaneously hypertensive rats (SHRsp). Both groups were followed for 6 weeks after 70% subtotal nephrectomy (SNX) or sham operation. RESULTS Blood pressures in the SNX group at the end of the experiment were 193 +/- 3 mmHg in TGR and 199 +/- 5 mmHg in SHRsp. The final C(in) was 306 +/- 68 microliters/min per 100 g body weight in TGR that had undergone SNX and 550 +/- 93 microliters/min per 100 g body weight in SHR that had undergone SNX (P < 0.02), whereas inulin clearance (C(in)) in sham-operated pair-fed TGR and SHRsp controls did not differ from each other. The glomerulosclerosis index was 1.75 +/- 0.08 in perfusion-fixed TGR that had undergone SNX versus 1.21 +/- 0.03 in SHR that had undergone SNX (P < 0.005). In addition, the media thickness of preglomerular vessels was significantly greater in TGR that had undergone SNX (7.48 +/- 0.79 microns) than it was in SHRsp that had undergone SNX (5.27 +/- 1.38 microns, P < 0.02). Rat renal renin messenger RNA (mRNA) expression and, in parallel, mouse REN-2 gene expression were lower in TGR after SNX. Plasma renin and angiotensin II (ANG II) concentrations were reduced to a similar extent in both SNX groups, but plasma prorenin was higher in TGR that had undergone SNX than it was in SHRsp that had undergone SNX. The angiotensin II:I ratio in the kidney was significantly higher in TGR (P < 0.01). There was no significant difference between sham-operated or subtotally nephrectomized TGR and SHRsp with respect to angiotensin type 1 mRNA and angiotensinogen mRNA. The renal angiotensin converting enzyme activity, however, was significantly higher in sham operated and subtotally nephrectomized TGR than it was in sham operated SHRsp and in SHRsp that had undergone SNX. CONCLUSION Deterioration of renal function is accelerated in subtotally nephrectomized transgenic rats [TGR(mREN2)27] compared with that in comparably hypertensive SHRsp despite suppressed circulating active mRNA and decreased renal renin mRNA. Although alternative explanations are possible, this observation is consistent with a role for local ANG II in the genesis of glomerulosclerosis.
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Medarde M, Mesot J, Rosenkranz S, Radaelli P, Marshall W, Klotz S, Loveday JS, Hamel G, Hull S. Neutron diffraction studies of the metallization process in RNiO 3perovskites ( R= rare earth). Acta Crystallogr A 1996. [DOI: 10.1107/s0108767396078476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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140
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Marshall WG, Nelmes RJ, Loveday JS, Besson JM, Klotz S, Hamel G. Neutron attenuation corrections for the Paris–Edinburgh high-pressure cell. Acta Crystallogr A 1996. [DOI: 10.1107/s0108767396077744] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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141
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Finney JL, Lobban C, Klotz S, Besson JM. Pressure-induced phase transformations in ice at low temperature. Acta Crystallogr A 1996. [DOI: 10.1107/s0108767396078208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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142
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Klotz S. New applications of the Paris–Edinburgh cell: neutrons and X-rays. Acta Crystallogr A 1996. [DOI: 10.1107/s0108767396078026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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143
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Loveday JS, Nelmes RJ, Marshall WG, Besson JM, Klotz S, Hamel G. Neutron diffraction studies of hydrogen-bonded ices. Acta Crystallogr A 1996. [DOI: 10.1107/s0108767396078270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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144
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Klotz S. [Nursing and care of patients with cystic fibrosis]. KINDERKRANKENSCHWESTER : ORGAN DER SEKTION KINDERKRANKENPFLEGE 1996; 15:278-80. [PMID: 8718203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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145
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Loveday JS, Nelmes RJ, Marshall WG, Besson JM, Klotz S, Hamel G. Structure of deuterated phase-IV ammonia. PHYSICAL REVIEW LETTERS 1996; 76:74-77. [PMID: 10060437 DOI: 10.1103/physrevlett.76.74] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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146
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Nelmes RJ, Loveday JS, Wilson RM, Marshall WG, Besson JM, Klotz S, Hamel G, Aselage TL, Hull S. Observation of inverted-molecular compression in boron carbide. PHYSICAL REVIEW LETTERS 1995; 74:2268-2271. [PMID: 10057885 DOI: 10.1103/physrevlett.74.2268] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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147
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Besson JM, Pruzan P, Klotz S, Hamel G, Silvi B, Nelmes RJ, Loveday JS, Wilson RM, Hull S. Variation of interatomic distances in ice VIII to 10 GPa. PHYSICAL REVIEW. B, CONDENSED MATTER 1994; 49:12540-12550. [PMID: 10010155 DOI: 10.1103/physrevb.49.12540] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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148
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Nelmes RJ, Loveday JS, Wilson RM, Besson JM, Pruzan P, Klotz S, Hamel G, Hull S. Neutron diffraction study of the structure of deuterated ice VIII to 10 GPa. PHYSICAL REVIEW LETTERS 1993; 71:1192-1195. [PMID: 10055473 DOI: 10.1103/physrevlett.71.1192] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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149
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Loveday JS, Wilson RM, Nelmes RJ, Besson JM, Klotz S, Hamel G, Hull S. Data collection and analysis techniques for accurate neutron powder diffraction studies above 10 GPa. Acta Crystallogr A 1993. [DOI: 10.1107/s0108767378087887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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150
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Nelmes RJ, Loveday JS, Wilson RM, Besson JM, Klotz S, Hamel G, Hull S. Crystal-structure studies to 10 GPa using neutron powder diffraction techniques. Acta Crystallogr A 1993. [DOI: 10.1107/s0108767378087899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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