Stephen K Obaro, MBBS, PhD

  • 4167 Citations
  • 28 h-Index
1993 …2020

Research output per year

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Research Output

2020

A mosaic tetracycline resistance gene tet(S/M) detected in an MDR pneumococcal CC230 lineage that underwent capsular switching in South Africa

Global Pneumococcal Sequencing Consortium, Mar 1 2020, In : Journal of Antimicrobial Chemotherapy. 75, 3, p. 512-520 9 p.

Research output: Contribution to journalArticle

Open Access

Neonatal outcomes associated with maternal recto-vaginal colonization with extended-spectrum β-lactamase producing Enterobacteriaceae in Nigeria: a prospective, cross-sectional study

Neemann, K., Olateju, E. K., Izevbigie, N., Akaba, G., Olanipekun, G. M., Richard, J. C., Duru, C. I., Kocmich, N. J., Samson, K. K., Rezac-Elgohary, A., Anigilaje, E. A., Yunusa, T., Megafu, C. O. N., Ajose, T. O., Medugu, N., Meza, J. & Obaro, S., Apr 2020, In : Clinical Microbiology and Infection. 26, 4, p. 463-469 7 p.

Research output: Contribution to journalArticle

1 Scopus citations

Paper-based microchip electrophoresis for point-of-care hemoglobin testing

Hasan, M. N., Fraiwan, A., An, R., Alapan, Y., Ung, R., Akkus, A., Xu, J. Z., Rezac, A. J., Kocmich, N. J., Creary, M. S., Oginni, T., Olanipekun, G. M., Hassan-Hanga, F., Jibir, B. W., Gambo, S., Verma, A. K., Bharti, P. K., Riolueang, S., Ngimhung, T., Suksangpleng, T. & 9 others, Thota, P., Werner, G., Shanmugam, R., Das, A., Viprakasit, V., Piccone, C. M., Little, J. A., Obaro, S. K. & Gurkan, U. A., Apr 7 2020, In : Analyst. 145, 7, p. 2525-2542 18 p.

Research output: Contribution to journalArticle

Open Access

Towards understanding global patterns of antimicrobial use and resistance in neonatal sepsis: Insights from the NeoAMR network

Li, G., Bielicki, J. A., Ahmed, A. S. M. N. U., Islam, M. S., Berezin, E. N., Gallacci, C. B., Guinsburg, R., Da Silva Figueiredo, C. E., Santarone Vieira, R., Silva, A. R., Teixeira, C., Turner, P., Nhan, L., Orrego, J., Pérez, P. M., Qi, L., Papaevangelou, V., Triantafyllidou, P., Iosifidis, E., Roilides, E. & 43 others, Sarafidis, K., Jinka, D. R., Nayakanti, R. R., Kumar, P., Gautam, V., Prakash, V., Seeralar, A., Murki, S., Kandraju, H., Singh, S., Kumar, A., Lewis, L., Pukayastha, J., Nangia, S., Yogesha, K. N., Chaurasia, S., Chellani, H., Obaro, S., Dramowski, A., Bekker, A., Whitelaw, A., Thomas, R., Velaphi, S. C., Ballot, D. E., Nana, T., Reubenson, G., Fredericks, J., Anugulruengkitt, S., Sirisub, A., Wong, P., Lochindarat, S., Boonkasidecha, S., Preedisripipat, K., Cressey, T. R., Paopongsawan, P., Lumbiganon, P., Pongpanut, D., Sukrakanchana, P. O., Musoke, P., Olson, L., Larsson, M., Heath, P. T. & Sharland, M., Jan 1 2020, In : Archives of Disease in Childhood. 105, 1, p. 26-31 6 p.

Research output: Contribution to journalArticle

Open Access
2 Scopus citations
2019

Emergence of New Delhi metallo-β-lactamase (NDM-5) in Klebsiella quasipneumoniae from neonates in a Nigerian hospital

Brinkac, L. M., White, R., D'Souza, R., Nguyen, K., Obaro, S. K. & Fouts, D. E., Mar 1 2019, In : mSphere. 4, 2, e00685-18.

Research output: Contribution to journalArticle

Open Access
6 Scopus citations

Erratum: Status of retinoids and carotenoids and associations with clinical outcomes in maternal-infant pairs in Nigeria. (Nutrients 2018, 10, 1286)

Hanson, C., Lyden, E., Anderson-Berry, A., Kocmich, N., Rezac, A., Delair, S., Furtado, J., Van Ormer, M., Izevbigie, N., Olateju, E. K., Akaba, G. O., Anigilaje, E. A., Yunusa, T. & Obaro, S., Feb 2019, In : Nutrients. 11, 2, 396.

Research output: Contribution to journalComment/debate

Open Access
Open Access
18 Scopus citations

Pulmonary hypertension and right ventricular function in Nigerian children with sickle cell anaemia

Peter, I. D., Asani, M. O., Abdullahi, S. U., Aliyu, I., Obaro, S. K. & Bode-Thomas, F., Aug 1 2019, In : Transactions of the Royal Society of Tropical Medicine and Hygiene. 113, 8, p. 489-496 8 p., trz038.

Research output: Contribution to journalArticle

Open Access
1 Scopus citations

Updating the diagnosis of bacterial meningitis

Obaro, S., Nov 2019, In : The Lancet Infectious Diseases. 19, 11, p. 1160-1161 2 p.

Research output: Contribution to journalComment/debate

Urogenital schistosomiasis is associated with signatures of microbiome dysbiosis in Nigerian adolescents

Ajibola, O., Rowan, A. D., Ogedengbe, C. O., Mshelia, M. B., Cabral, D. J., Eze, A. A., Obaro, S. & Belenky, P., Dec 1 2019, In : Scientific reports. 9, 1, 829.

Research output: Contribution to journalArticle

5 Scopus citations
2018

A comparison of vitamin E status and associated pregnancy outcomes in maternal–infant dyads between a Nigerian and a United States population

Cave, C., Hanson, C., Schumacher, M., Lyden, E., Furtado, J., Obaro, S., Delair, S., Kocmich, N., Rezac, A., Izevbigie, N. I., Van nOrmer, M., Kamil, A., McGinn, E., Rilett, K., Elliott, E., Johnson, R., Weishaar, K., Olateju, E. K., Akaba, G. A., Anigilaje, E. A. & 2 others, Tahiru, T. & Anderson-Berry, A., Sep 14 2018, In : Nutrients. 10, 9, 1300.

Research output: Contribution to journalArticle

1 Scopus citations

Acquisition of virulence genes by a carrier strain gave rise to the ongoing epidemics of meningococcal disease in West Africa

Brynildsrud, O. B., Eldholm, V., Bohlin, J., Uadiale, K., Obaro, S. & Caugant, D. A., May 22 2018, In : Proceedings of the National Academy of Sciences of the United States of America. 115, 21, p. 5510-5515 6 p.

Research output: Contribution to journalArticle

20 Scopus citations

Aetiology of neonatal sepsis in Nigeria, and relevance of group b streptococcus: A systematic review

Medugu, N., Iregbu, K., Tam, P. Y. I. & Obaro, S., Jul 2018, In : PloS one. 13, 7, e0200350.

Research output: Contribution to journalReview article

4 Scopus citations

A meta-analysis of antimicrobial susceptibility profiles for pneumococcal pneumonia in sub-Saharan Africa

Iroh Tam, P. Y., Sadoh, A. E. & Obaro, S. K., Jan 2 2018, In : Paediatrics and International Child Health. 38, 1, p. 7-15 9 p.

Research output: Contribution to journalReview article

4 Scopus citations

Detection of Streptococcus pneumoniae from culture-negative dried blood spots by real-time PCR in Nigerian children with acute febrile illness

Iroh Tam, P. Y., Hernandez-Alvarado, N., Schleiss, M. R., Yi, A. J., Hassan-Hanga, F., Onuchukwu, C., Umoru, D. & Obaro, S. K., Sep 10 2018, In : BMC Research Notes. 11, 1, 657.

Research output: Contribution to journalArticle

1 Scopus citations

Determinants of postoperative morbidity and mortality in children managed for typhoid intestinal perforation in Kano Nigeria

Anyanwu, L. J., Mohammad, A., Abdullahi, L., Farinyaro, A. & Obaro, S., Apr 2018, In : Journal of pediatric surgery. 53, 4, p. 847-852 6 p.

Research output: Contribution to journalArticle

2 Scopus citations

Invasive non-typhoidal Salmonella in sickle cell disease in Africa: Is increased gut permeability the missing link?

Lim, S. H., Methé, B. A., Knoll, B. M., Morris, A. & Obaro, S. K., Aug 30 2018, In : Journal of Translational Medicine. 16, 1, 239.

Research output: Contribution to journalComment/debate

4 Scopus citations

Status of retinoids and carotenoids and associations with clinical outcomes in maternal-infant pairs in Nigeria

Hanson, C., Lyden, E., Anderson-Berry, A., Kocmich, N., Rezac, A., Delair, S., Furtado, J., Van Ormer, M., Izevbigie, N. I., Olateju, E. D., Adaba, G. A., Anigilaje, E. A., Tahiru, T. & Obaro, S., Sep 12 2018, In : Nutrients. 10, 9, 1286.

Research output: Contribution to journalArticle

4 Scopus citations

The phylogeography and incidence of multi-drug resistant typhoid fever in sub-Saharan Africa

Park, S. E., Pham, D. T., Boinett, C., Wong, V. K., Pak, G. D., Panzner, U., Espinoza, L. M. C., von Kalckreuth, V., Im, J., Schütt-Gerowitt, H., Crump, J. A., Breiman, R. F., Adu-Sarkodie, Y., Owusu-Dabo, E., Rakotozandrindrainy, R., Soura, A. B., Aseffa, A., Gasmelseed, N., Keddy, K. H., May, J. & 50 others, Sow, A. G., Aaby, P., Biggs, H. M., Hertz, J. T., Montgomery, J. M., Cosmas, L., Olack, B., Fields, B., Sarpong, N., Razafindrabe, T. J. L., Raminosoa, T. M., Kabore, L. P., Sampo, E., Teferi, M., Yeshitela, B., El Tayeb, M. A., Sooka, A., Meyer, C. G., Krumkamp, R., Dekker, D. M., Jaeger, A., Poppert, S., Tall, A., Niang, A., Bjerregaard-Andersen, M., Løfberg, S. V., Seo, H. J., Jeon, H. J., Deerin, J. F., Park, J., Konings, F., Ali, M., Clemens, J. D., Hughes, P., Sendagala, J. N., Vudriko, T., Downing, R., Ikumapayi, U. N., Mackenzie, G. A., Obaro, S., Argimon, S., Aanensen, D. M., Page, A., Keane, J. A., Duchene, S., Dyson, Z., Holt, K. E., Dougan, G., Marks, F. & Baker, S., Dec 1 2018, In : Nature communications. 9, 1, 5094.

Research output: Contribution to journalArticle

12 Scopus citations

Typhoid fever: Tracking the trend in Nigeria

Akinyemi, K. O., Oyefolu, A. O. B., Mutiu, W. B., Iwalokun, B. A., Ayeni, E. S., Ajose, S. O. & Obaro, S. K., 2018, In : American Journal of Tropical Medicine and Hygiene. 99, 3, p. 41-47 7 p.

Research output: Contribution to journalArticle

6 Scopus citations
2017

Childhood pneumococcal disease in Africa – A systematic review and meta-analysis of incidence, serotype distribution, and antimicrobial susceptibility

Iroh Tam, P. Y., Thielen, B. K., Obaro, S. K., Brearley, A. M., Kaizer, A. M., Chu, H. & Janoff, E. N., Apr 4 2017, In : Vaccine. 35, 15, p. 1817-1827 11 p.

Research output: Contribution to journalReview article

16 Scopus citations

Cost-effectiveness of expanding childhood routine immunization against Neisseria meningitidis serogroups C, W and Y with a quadrivalent conjugate vaccine in the African meningitis belt

Kuznik, A., Iliyasu, G., Lamorde, M., Mahmud, M., Musa, B. M., Nashabaru, I., Obaro, S., Mohammed, I. & Habib, A. G., Nov 2017, In : PloS one. 12, 11, e0188595.

Research output: Contribution to journalArticle

3 Scopus citations

Development of ELISAs for diagnosis of acute typhoid fever in Nigerian children

Felgner, J., Jain, A., Nakajima, R., Liang, L., Jasinskas, A., Gotuzzo, E., Vinetz, J. M., Miyajima, F., Pirmohamed, M., Hassan-Hanga, F., Umoru, D., Jibir, B. W., Gambo, S., Olateju, K., Felgner, P. L., Obaro, S. & Davies, D. H., Jun 22 2017, In : PLoS neglected tropical diseases. 11, 6, e0005679.

Research output: Contribution to journalArticle

7 Scopus citations

Increased memory phenotypes of CD4+ and CD8+ t cells in children with sickle cell anaemia in Tanzania

Balandya, E., Reynolds, T., Aboud, S., Obaro, S. & Makani, J., 2017, In : Tanzania Journal of Health Research. 19, 2

Research output: Contribution to journalArticle

The unrecognized burden of typhoid fever

Obaro, S. K., Iroh Tam, P. Y. & Mintz, E. D., Mar 4 2017, In : Expert Review of Vaccines. 16, 3, p. 249-260 12 p.

Research output: Contribution to journalReview article

16 Scopus citations
2016

Alteration of lymphocyte phenotype and function in sickle cell anemia: Implications for vaccine responses

Balandya, E., Reynolds, T., Obaro, S. & Makani, J., Sep 1 2016, In : American Journal of Hematology. 91, 9, p. 938-946 9 p.

Research output: Contribution to journalReview article

17 Scopus citations

An extended genotyping framework for Salmonella enterica serovar Typhi, the cause of human typhoid

Wong, V. K., Baker, S., Connor, T. R., Pickard, D., Page, A. J., Dave, J., Murphy, N., Holliman, R., Sefton, A., Millar, M., Dyson, Z. A., Dougan, G., Holt, K. E., Parkhill, J., Kingsley, R. A., Thomson, N. R., Keane, J. A., Hadfield, J., Klemm, E. J., Harris, S. R. & 63 others, Cain, A. K., Kariuki, S., Okoro, C., MacLennan, C. A., Vu Thieu, N. T., Thanh, D. P., Thompson, C., Dolecek, C., Campbell, J. I., Thwaites, G., Farrar, J., Newton, P. N., Dance, D., Turner, P., Mulholland, E. K., Hawkey, J., Edwards, D. J., Feasey, N. A., Weill, F. X., Le Hello, S., Hart, P. J., Breiman, R. F., Onsare, R. S., Watson, C. H., Edmunds, W. J., Gordon, M. A., Heyderman, R. S., Msefula, C., Jacobs, J., Lunguya, O., Chabalgoity, J. A., Kama, M., Jenkins, K., Dutta, S., Marks, F., Campos, J., Obaro, S., Keddy, K. H., Smith, A. M., Parry, C. M., Karkey, A., Dongol, S., Basnyat, B., Arjyal, A., Dufour, M., Bandaranayake, D., Toleafoa, T. N., Singh, S. P., Hatta, M., Davong, V., Isaia, L., Wijedoru, L., Crump, J. A., De Pinna, E., Nair, S., Nilles, E. J., Soeng, S., Valcanis, M., Powling, J., Dimovski, K., Hogg, G., Mather, A. E. & Amos, B., 2016, In : Nature communications. 7, 12827.

Research output: Contribution to journalArticle

42 Scopus citations

Challenges in the etiology and diagnosis of acute febrile illness in children in low- and middle- income countries

Tam, P. Y. I., Obaro, S. K. & Storch, G., Jun 10 2016, In : Journal of the Pediatric Infectious Diseases Society. 5, 2, p. 190-205 16 p., piw016.

Research output: Contribution to journalArticle

14 Scopus citations

Control of meningitis outbreaks in the African meningitis belt

Obaro, S. K. & Habib, A. G., Apr 1 2016, In : The Lancet Infectious Diseases. 16, 4, p. 400-402 3 p.

Research output: Contribution to journalComment/debate

5 Scopus citations

Hydroxyurea Therapy for Children With Sickle Cell Anemia in Sub-Saharan Africa: Rationale and Design of the REACH Trial

For the REACH Investigators, Jan 1 2016, In : Pediatric Blood and Cancer. 63, 1, p. 98-104 7 p.

Research output: Contribution to journalArticle

18 Scopus citations

Is integrating sickle cell disease and HIV screening logical?

Obaro, S., Mar 1 2016, In : The Lancet Global Health. 4, 3, p. e144-e145

Research output: Contribution to journalComment/debate

Molecular detection of Streptococcus pneumoniae on dried blood spots from febrile Nigerian children compared to culture

Tam, P. Y. I., Hernandez-Alvarado, N., Schleiss, M. R., Hassan-Hanga, F., Onuchukwu, C., Umoru, D. & Obaro, S. K., Mar 2016, In : PloS one. 11, 3, e0152253.

Research output: Contribution to journalArticle

7 Scopus citations

Molecular Surveillance Identifies Multiple Transmissions of Typhoid in West Africa

International Typhoid Consortium, Sep 22 2016, In : PLoS neglected tropical diseases. 10, 9, e0004781.

Research output: Contribution to journalArticle

21 Scopus citations

Preventing Infections in Sickle Cell Disease: The Unfinished Business

Obaro, S. K. & Tam, P. Y. I., May 1 2016, In : Pediatric blood & cancer. 63, 5, p. 781-785 5 p.

Research output: Contribution to journalReview article

9 Scopus citations

Serodiagnosis of acute typhoid fever in nigerian pediatric cases by detection of serum IgA and IgG against hemolysin e and Lipopolysaccharide

Davies, D. H., Jain, A., Nakajima, R., Liang, L., Jasinskis, A., Supnet, M., Felgner, P. L., Teng, A., Pablo, J., Molina, D. M. & Obaro, S. K., Aug 2016, In : American Journal of Tropical Medicine and Hygiene. 95, 2, p. 431-439 9 p.

Research output: Contribution to journalArticle

8 Scopus citations

Sickle-cell disease in Nigerian Children: Parental knowledge and laboratory results

Obaro, S. K., Daniel, Y., Lawson, J. O., Hsu, W. W., Dada, J., Essen, U., Ibrahim, K., Akindele, A., Brooks, K., Olanipekun, G., Ajose, T., Stewart, C. E. & Inusa, B. P. D., Apr 1 2016, In : Public Health Genomics. 19, 2, p. 102-107 6 p.

Research output: Contribution to journalArticle

1 Scopus citations

Surveillance in Africa's meningitis belt: time for new targets?

Obaro, S. K., Aug 1 2016, In : The Lancet Global Health. 4, 8, p. e514-e515

Research output: Contribution to journalComment/debate

1 Scopus citations
2015

Hydroxyurea for sickle-cell anaemia in Africa: Mind the gap

Obaro, S. K., Mar 1 2015, In : The Lancet Global Health. 3, 3, p. e124-e125

Research output: Contribution to journalComment/debate

4 Scopus citations

Neonatal group B streptococcus disease in developing countries: Are we ready to deploy a vaccine?

Iroh Tam, P. Y., Delair, S. F. & Obaro, S. K., Nov 2 2015, In : Expert Review of Vaccines. 14, 11, p. 1401-1403 3 p.

Research output: Contribution to journalReview article

5 Scopus citations

Phylogeographical analysis of the dominant multidrug-resistant H58 clade of Salmonella Typhi identifies inter-and intracontinental transmission events

Wong, V. K., Baker, S., Pickard, D. J., Parkhill, J., Page, A. J., Feasey, N. A., Kingsley, R. A., Thomson, N. R., Keane, J. A., Weill, F. X., Edwards, D. J., Hawkey, J., Harris, S. R., Mather, A. E., Cain, A. K., Hadfield, J., Hart, P. J., Thieu, N. T. V., Klemm, E. J., Glinos, D. A. & 54 others, Breiman, R. F., Watson, C. H., Kariuki, S., Gordon, M. A., Heyderman, R. S., Okoro, C., Jacobs, J., Lunguya, O., Edmunds, W. J., Msefula, C., Chabalgoity, J. A., Kama, M., Jenkins, K., Dutta, S., Marks, F., Campos, J., Thompson, C., Obaro, S., Maclennan, C. A., Dolecek, C., Keddy, K. H., Smith, A. M., Parry, C. M., Karkey, A., Mulholland, E. K., Campbell, J. I., Dongol, S., Basnyat, B., Dufour, M., Bandaranayake, D., Naseri, T. T., Singh, S. P., Hatta, M., Newton, P., Onsare, R. S., Isaia, L., Dance, D., Davong, V., Thwaites, G., Wijedoru, L., Crump, J. A., De Pinna, E., Nair, S., Nilles, E. J., Thanh, D. P., Turner, P., Soeng, S., Valcanis, M., Powling, J., Dimovski, K., Hogg, G., Farrar, J., Holt, K. E. & Dougan, G., May 27 2015, In : Nature Genetics. 47, 6, p. 632-639 8 p.

Research output: Contribution to journalArticle

189 Scopus citations

Salmonella bacteremia among children in central and Northwest Nigeria, 2008-2015

Obaro, S. K., Hassan-Hanga, F., Olateju, E. K., Umoru, D., Lawson, L., Olanipekun, G., Ibrahim, S., Munir, H., Ihesiolor, G., Maduekwe, A., Ohiaeri, C., Adetola, A., Shetima, D., Jibir, B. W., Nakaura, H., Kocmich, N., Ajose, T., Idiong, D., Masokano, K., Ifabiyi, A. & 11 others, Ihebuzor, N., Chen, B., Meza, J., Akindele, A., Rezac-Elgohary, A., Olaosebikan, R., Suwaid, S., Gambo, M., Alter, R., Davies, H. D. & Fey, P. D., Nov 1 2015, In : Clinical Infectious Diseases. 61, p. S325-S331

Research output: Contribution to journalArticle

19 Scopus citations

Simplified antibiotic regimens for neonatal sepsis - AFRINEST(3)

Delair, S. & Obaro, S. K., Oct 3 2015, In : The Lancet. 386, 10001, 1 p.

Research output: Contribution to journalLetter

2014
1 Scopus citations

Poliomyelitis in Nigeria

Obaro, S., Olaosebikan, R. & Ayede, A. I., Jun 2014, In : The Lancet Global Health. 2, 6, p. e319

Research output: Contribution to journalLetter

2013

Comparative effectiveness of congregation- versus clinic-based approach to prevention of mother-to-child HIV transmission: Study protocol for a cluster randomized controlled trial

Ezeanolue, E. E., Obiefune, M. C., Yang, W., Obaro, S. K., Ezeanolue, C. O. & Ogedegbe, G. G., Jun 8 2013, In : Implementation Science. 8, 1, 62.

Research output: Contribution to journalArticle

22 Scopus citations
2012

Does sickle cell disease protect against HIV/AIDS?

Obaro, S., Nov 2012, In : Sexually Transmitted Infections. 88, 7, 1 p.

Research output: Contribution to journalComment/debate

6 Scopus citations

Intracontinental spread of human invasive Salmonella Typhimurium pathovariants in sub-Saharan Africa

Okoro, C. K., Kingsley, R. A., Connor, T. R., Harris, S. R., Parry, C. M., Al-Mashhadani, M. N., Kariuki, S., Msefula, C. L., Gordon, M. A., De Pinna, E., Wain, J., Heyderman, R. S., Obaro, S., Alonso, P. L., Mandomando, I., MacLennan, C. A., Tapia, M. D., Levine, M. M., Tennant, S. M., Parkhill, J. & 1 others, Dougan, G., Nov 2012, In : Nature Genetics. 44, 11, p. 1215-1221 7 p.

Research output: Contribution to journalArticle

219 Scopus citations

Safety of the recombinant cholera toxin B subunit, killed whole-cell (rBS-WC) Oral Cholera vaccine in pregnancy

Hashim, R., Khatib, A. M., Enwere, G., Park, J. K., Reyburn, R., Ali, M., Chang, N. Y., Kim, D. R., Ley, B., Thriemer, K., Lopez, A. L., Clemens, J. D., Deen, J. L., Shin, S., Schaetti, C., Hutubessy, R., Aguado, M. T., Kieny, M. P., Sack, D., Obaro, S. & 5 others, Shaame, A. J., Ali, S. M., Saleh, A. A., von Seidlein, L. & Jiddawi, M. S., Jul 2012, In : PLoS neglected tropical diseases. 6, 7, e1743.

Research output: Contribution to journalArticle

26 Scopus citations
2011

5 versus 10 days of ceftriaxone for bacterial meningitis in children

Obaro, S., Nov 5 2011, In : The Lancet. 378, 9803, p. 1624-1625 2 p.

Research output: Contribution to journalLetter

1 Scopus citations

Artesunate for severe malaria in African children

Obaro, S. K., Apr 2 2011, In : The Lancet. 377, 9772, p. 1153-1154 2 p.

Research output: Contribution to journalLetter