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Background Plasmodium vivax has been proposed to infect and replicate in the human spleen and bone marrow. Compared to Plasmodium falciparum, which is known to undergo microvascular tissue sequestration, little is known about the behavior of P. vivax outside of the circulating compartment. This may be due in part to difficulties in studying parasite location and activity in life. Methods and findings To identify organ-specific changes during the early stages of P. vivax infection, we performed 18-F fluorodeoxyglucose (FDG) positron emission tomography/magnetic resonance imaging (PET/MRI) at baseline and just prior to onset of clinical illness in P. vivax experimentally induced blood-stage malaria (IBSM) and compared findings to P. falciparum IBSM. Seven healthy, malaria-naive participants were enrolled from 3 IBSM trials: NCT02867059, ACTRN12616000174482, and ACTRN12619001085167. Imaging took place between 2016 and 2019 at the Herston Imaging Research Facility, Australia. Postinoculation imaging was performed after a median of 9 days in both species (n = 3 P. vivax; n = 4 P. falciparum). All participants were aged between 19 and 23 years, and 6/7 were male. Splenic volume (P. vivax: +28.8% [confidence interval (CI) +10.3% to +57.3%], P. falciparum: +22.9 [CI -15.3% to +61.1%]) and radiotracer uptake (P. vivax: +15.5% [CI -0.7% to +31.7%], P. falciparum: +5.5% [CI +1.4% to +9.6%]) increased following infection with each species, but more so in P. vivax infection (volume: p = 0.72, radiotracer uptake: p = 0.036). There was no change in FDG uptake in the bone marrow (P. vivax: +4.6% [CI -15.9% to +25.0%], P. falciparum: +3.2% [CI -3.2% to +9.6%]) or liver (P. vivax: +6.2% [CI -8.7% to +21.1%], P. falciparum: -1.4% [CI -4.6% to +1.8%]) following infection with either species. In participants with P. vivax, hemoglobin, hematocrit, and platelet count decreased from baseline at the time of postinoculation imaging. Decrements in hemoglobin and hematocrit were significantly greater in participants with P. vivax infection compared to P. falciparum. The main limitations of this study are the small sample size and the inability of this tracer to differentiate between host and parasite metabolic activity. Conclusions PET/MRI indicated greater splenic tropism and metabolic activity in early P. vivax infection compared to P. falciparum, supporting the hypothesis of splenic accumulation of P. vivax very early in infection. The absence of uptake in the bone marrow and liver suggests that, at least in early infection, these tissues do not harbor a large parasite biomass or do not provoke a prominent metabolic response. PET/MRI is a safe and noninvasive method to evaluate infection-associated organ changes in morphology and glucose metabolism., Author(s): John Woodford 1,2,*, Ashley Gillman 3, Peter Jenvey 4, Jennie Roberts 4, Stephen Woolley 1,5, Bridget E. Barber 1,6, Melissa Fernandez 1, Stephen Rose 3, Paul Thomas 7, Nicholas [...]

Kansas City Lightning: The Rise and Times of Charlie Parker, by Stanley Crouch. New York: HarperCollins, 2013. $27.99 hardback. 365 pages. Reviewed by John Woodford. This masterwork by Stanley Crouch [...]

The Black Cultural Front: Black Writers and Artists of the Depression Generation, by Brian Dolinar. Jackson: University of Mississippi Press, 2012. $60 hardcover; $34 Amazon online. Reviewed by John Woodford. [...]

Background The extent of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) exposure and transmission in Mali and the surrounding region is not well understood. We aimed to estimate the cumulative incidence of SARS-CoV-2 in 3 communities and understand factors associated with infection. Methods Between July 2020 and January 2021, we collected blood samples and demographic, social, medical, and self-reported symptoms information from residents aged 6 months and older over 2 study visits. SARS-CoV-2 antibodies were measured using a highly specific 2-antigen enzyme-linked immunosorbent assay optimized for use in Mali. We calculated cumulative adjusted seroprevalence for each community and evaluated factors associated with serostatus at each visit by univariate and multivariate analysis. Results Overall, 94.8% (2533/2672) of participants completed both study visits. A total of 31.3% (837/2672) were aged <10 years, 27.6% (737/2672) were aged 10–17 years, and 41.1% (1098/2572) were aged ≥18 years. The cumulative SARS-CoV-2 exposure rate was 58.5% (95% confidence interval, 47.5–69.4). This varied between sites and was 73.4% in the urban community of Sotuba, 53.2% in the rural town of Bancoumana, and 37.1% in the rural village of Donéguébougou. Study site and increased age were associated with serostatus at both study visits. There was minimal difference in reported symptoms based on serostatus. Conclusions The true extent of SARS-CoV-2 exposure in Mali is greater than previously reported and may now approach hypothetical "herd immunity" in urban areas. The epidemiology of the pandemic in the region may be primarily subclinical and within background illness rates. [ABSTRACT FROM AUTHOR]

'Conversations with Richard Wright, ' a collection of Wright's press and radio interviews, successfully brings out the consistency of his ethical and aesthetic thoughts and explains his concern for the blacks of the US and the problem of bigotry. In the short novel 'Rite of Passage' started in 1945, Wright describes this bigotry against urban blacks and their meaningless existence in new social units. Wright strongly believed that continued oppression would create destructive tendencies and that discrimination hampered the mental faculties of the blacks.

The poems in 'Minor Casualties, New and Selected Poems,' written by Robert Chrisman of the University of Michigan's English Department, Center for Afro-American and American studies and editor of The Black Scholar, deal with politics and love. Most of the poems in the volume have a modernist tone as they reveal the poet's mind. The poems in the last section are more impressionistic and personal than the poems in the first two sections.

“Near-frictionless carbon,” a form of amorphous hydrogenated diamondlike carbon developed at Argonne National Laboratory, has been investigated by neutron and x-ray reflectivity under ambient conditions, in vacuum, and at elevated temperature. A series of films was made with different ratios of hydrogen to carbon in the plasma; the deuterated counterparts were also synthesized. The details of scattering length density profiles, thickness, and surface and interfacial roughness of the films were obtained from neutron and x-ray reflectivity profiles. This allowed us to calculate the mass density and hydrogen composition of the bulk carbon film, leading to insight into the frictional properties. From the analysis we found that the magnitude of the scattering length density of the top surface layer was greatly affected by the experimental atmosphere in which the films were contained although the trend with hydrogen in the plasma remained the same. All samples were fitted with a three-layer model in addition to the substrate. [ABSTRACT FROM AUTHOR]

A form of hydrogenated diamond-like-carbon, “near-frictionless carbon,” developed at Argonne National Laboratory has been studied by several spectroscopic techniques to determine the hydrogen content and carbon bonding within the film. The techniques used include hydrogen forward scattering, ultraviolet Raman spectroscopy, Fourier transform infrared spectroscopy, near-edge x-ray absorption fine structure, and fluctuation microscopy. These complementary techniques reveal the different types of carbon bonding, such as sp2 and sp3, the medium-range order in the film, and its composition. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The NIST watt balance experiment is being completely rebuilt after its 1998 determination of the Planck constant. That measurement yielded a result with an approximately 1 X [10.sup.-7] relative standard […]