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The spread of SARS-CoV-2 cannot be well monitored and understood in areas without capacity for effective disease surveillance. Countries with a young population will have disproportionately large numbers of asymptomatic or pauci-symptomatic infections, further hindering detection of infection in the population. Sero-surveillance on a country-wide scale by trained medical professionals may be limited in scope in resource limited setting such as Mali. Novel ways of broadly sampling the human population in a non-invasive method would allow for large-scale surveillance at a reduced cost. Here we evaluate the collection of naturally bloodfed mosquitoes to test for human anti-SARS-CoV-2 antibodies in the laboratory and at five field locations in Mali. Immunoglobulin-G antibodies were found to be readily detectable within the mosquito bloodmeals by a bead-based immunoassay at least through 10 hours post-feeding with high sensitivity (0.900 ± 0.059) and specificity (0.924 ± 0.080), respectively, indicating that most blood-fed mosquitoes collected indoors during early morning hours (and thus, have likely fed the previous night) are viable samples for analysis. We find that reactivity to four SARS-CoV-2 antigens rose during the pandemic from pre-pandemic levels. Consistent with other sero-surveillance studies in Mali, crude seropositivity of blood sampled via mosquitoes was 6.3% in October/November 2020 over all sites, and increased to 25.1% overall, with the town closest to Bamako reaching 46.7% in February of 2021. Mosquito bloodmeals a viable target for conventional immunoassays, and therefore country-wide sero-surveillance of human diseases (both vector-borne and non-vector-borne) is attainable in areas where human-biting mosquitoes are common, and is an informative, cost-effective, non-invasive sampling option.

Background False positivity may hinder the utility of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) serological tests in sub-Saharan Africa. Methods From 312 Malian samples collected before 2020, we measured antibodies to the commonly tested SARS-CoV-2 antigens and 4 other betacoronaviruses by enzyme-linked immunosorbent assay (ELISA). In a subset of samples, we assessed antibodies to a panel of Plasmodium falciparum antigens by suspension bead array and functional antiviral activity by SARS-CoV-2 pseudovirus neutralization assay. We then evaluated the performance of an ELISA using SARS-CoV-2 spike protein and receptor-binding domain developed in the United States using Malian positive and negative control samples. To optimize test performance, we compared single- and 2-antigen approaches using existing assay cutoffs and population-specific cutoffs. Results Background reactivity to SARS-CoV-2 antigens was common in prepandemic Malian samples. The SARS-CoV-2 reactivity varied between communities, increased with age, and correlated negligibly/weakly with other betacoronavirus and P falciparum antibodies. No prepandemic samples demonstrated functional activity. Regardless of the cutoffs applied, test specificity improved using a 2-antigen approach. Test performance was optimal using a 2-antigen assay with population-specific cutoffs (sensitivity, 73.9% [95% confidence interval {CI}, 51.6–89.8]; specificity, 99.4% [95% CI, 97.7–99.9]). Conclusions We have addressed the problem of SARS-CoV-2 seroassay performance in Africa by using a 2-antigen assay with cutoffs defined by performance in the target population.

Malaria may affect the reliability of SARS-CoV-2 seroassay performance and limit understanding of SARS-CoV-2 epidemiology in malaria-endemic regions. We present our experience conducting SARS-CoV-2 serosurveillance in seasonal malaria-affected communities in Mali and discuss relevant literature regarding the effect of malaria on the performance of SARS-CoV-2 serodiagnostics, including approaches to minimize the effect of malaria-associated assay interference.

BACKGROUND: The extent of SARS-CoV-2 exposure and transmission in Mali and the surrounding region is not well understood, although infection has been confirmed in nearly 14,000 symptomatic individuals and their contacts since the first case in March 2020. We aimed to estimate the cumulative incidence of SARS-CoV-2 in three Malian communities, and understand factors associated with infection. METHODS: Between 27 July 2020 and 29 January 2021, we collected blood samples along with demographic, social, medical and self-reported symptoms information from residents aged 6 months and older in three study communities at two study visits. SARS-CoV-2 antibodies were measured using a highly specific two-antigen ELISA optimized for use in Mali. We calculated cumulative adjusted seroprevalence for each site and evaluated factors associated with serostatus at each visit by univariate and multivariate analysis. FINDINGS: Overall, 94.8% (2533/2672) of participants completed both study visits. A total of 50.3% (1343/2672) of participants were male, and 31.3% (837/2672) were aged

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, This study demonstrates a large, previously unquantified burden of SARS-COV-2 infection in the community in West Africa. In this young study population, there was limited evidence of severe illness and seropositivity rates that may approach hypothetical “herd immunity.”

Serological tests are an indispensable tool to understand the epidemiology of the SARS-CoV-2 pandemic, particularly in areas where molecular diagnostics are limited. Poor assay performance may hinder the utility of these tests, including high rates of false-positivity previously reported in sub-Saharan Africa. From 312 Malian samples collected prior to 2020, we measured antibodies to the commonly tested SARS-CoV-2 antigens and four other betacoronaviruses by ELISA, and assessed functional cross-reactivity in a subset by SARS-CoV-2 pseudovirus neutralization assay. We then evaluated the performance of an ELISA developed in the US, using two-antigen SARS-CoV-2 spike protein and receptor-binding domain. To optimize test performance, we compared single and two-antigen approaches using existing assay cutoffs and population-specific cutoffs for Malian control samples (positive and negative). Background reactivity to SARS-CoV-2 antigens was common in pre-pandemic samples compared to US controls (43.4% (135/311) for spike protein, 22.8% (71/312) for RBD, and 33.9% (79/233) for nucleocapsid protein). SARS-CoV-2 reactivity correlated weakly with other betacoronavirus reactivity, varied between Malian communities, and increased with age. No pre-pandemic samples demonstrated functional activity. Regardless of the cutoffs applied, specificity improved using a two-antigen approach. Test performance was optimal using a two-antigen assay with population-specific cutoffs derived from ROC curve analysis [Sensitivity: 73.9% (51.6-89.8), Specificity: 99.4% (97.7-99.9)]. In the setting of high background reactivity, such as sub-Saharan Africa, SARS-CoV-2 serological assays need careful qualification is to characterize the epidemiology of disease, prevent unnecessary harm, and allocate resources for targeted control measures.

Background: Serological tests are an indispensable tool to understand the epidemiology of the SARS-CoV-2 pandemic, particularly in areas where molecular diagnostics are limited. Poor assay performance may hinder the utility of these tests, including high rates of false-positivity previously reported in sub-Saharan Africa. Methods: From 312 Malian samples collected prior to 2020, we measured antibodies to the commonly tested SARS-CoV-2 antigens and four other betacoronaviruses by ELISA, and assessed functional cross-reactivity in a subset by SARS-CoV-2 pseudovirus neutralization assay. We then evaluated the performance of a two-antigen test developed in the US, using SARS-CoV-2 spike protein and receptor-binding domain ELISA measurements. To optimize test performance, we compared single and two-antigen approaches using existing assay cutoffs and population-specific cutoffs for Malian control samples (positive and negative). Findings: Background reactivity to SARS-CoV-2 antigens was common in pre-pandemic samples compared to US controls (43·4% (135/311) for spike protein, 22·8% (71/312) for RBD, and 33·9% (79/233) for nucleocapsid protein). SARS-CoV-2 reactivity correlated weakly with other betacoronavirus reactivity, varied between Malian communities, and increased with age. No pre-pandemic samples demonstrated functional activity. Regardless of the cutoffs applied, specificity improved using a two-antigen approach. Test performance was optimal using a two-antigen assay with population-specific cutoffs derived from ROC curve analysis [Sensitivity: 73·9% (51·6-89·8), Specificity: 99·4% (97·7-99·9)]. Interpretation: In the setting of high background reactivity, such as sub-Saharan Africa, SARS-CoV-2 serological assays need careful qualification is to characterize the epidemiology of disease, prevent unnecessary harm, and allocate resources for targeted control measures. Funding: This project was funded by the Intramural Research Program of the National Institute of Allergy and Infectious Diseases, as well as the National Cancer Institute, National Institutes of Health. Declaration of Interests: The authors declare no conflicts of interest. Ethics Approval Statement: All pre-pandemic samples were collected during NIH-sponsored studies that were approved by the Malian USTTB FMPOS human research ethics committee and the NIAID/NIH institutional review board. Convalescent PCR-confirmed COVID-19 US positive control samples (n=10) were provided by the Adventist Hospital, Maryland. De-identified residual clinical samples for non-human subject research were obtained in accordance with 45 CFR 46. Convalescent samples were collected as part of a Public Health surveillance activity in collaboration with the Malian Ministry of Health COVID-19 Coordination Unit and with the approval of the USTTB FMOS-FAPH ethics committee (No2020/114/CE/FMOS/FAPH).

Endothelial activation and microvascular dysfunction are key pathogenic processes in severe malaria. We evaluated the early role of these processes in experimentally induced Plasmodium falciparum and P. vivax infection. Participants were enrolled in induced blood-stage malaria clinical trials. Plasma osteoprotegerin, angiopoietin-2, and von Willebrand Factor (vWF) levels were measured as biomarkers of endothelial activation. Microvascular function was assessed using peripheral arterial tonometry and near-infrared spectroscopy, and the endothelial glycocalyx was assessed by sublingual videomicroscopy and measurement of biomarkers of degradation. Forty-five healthy, malaria-naive participants were recruited from 5 studies. Osteoprotegerin and vWF levels increased in participants following inoculation with P. vivax (n = 16) or P. falciparum (n = 15), with the angiopoietin-2 level also increasing in participants following inoculation with P. falciparum For both species, the most pronounced increase was seen in osteoprotegerin. This was particularly marked in participants inoculated with P. vivax, where the osteoprotegerin level correlated with the levels of parasitemia and the malaria clinical score. There were no changes in measures of endothelial glycocalyx or microvascular function. Plasma biomarkers of endothelial activation increased in early P. falciparum and P. vivax infection and preceded changes in the endothelial glycocalyx or microvascular function. The more pronounced increase in osteoprotegerin suggests that this biomarker may play a role in disease pathogenesis. Published version

There is clinical uncertainty as to the testing of serum 25--Hydroxy vitamin D (25[OH]D) concentrations and when to use high-dose supplementation. Data show that there has been a rapid increase in the number of tests performed within the Northumbria Healthcare NHS Foundation Trust over the past 8 years and an increase in high-dose supplementation over the past 5 years. We performed a retrospective analysis of the 25(OH)D test requests over the period from January to -October 2017. A total of 17,405 tests were performed in this time period. The overall average concentration was 57.5 nmol/L and this figure was similar across age groups, although a larger proportion of patients aged over 75 had a concentration

Background MMV390048 is the first Plasmodium phosphatidylinositol 4-kinase inhibitor to reach clinical development as a new antimalarial. We aimed to characterize the safety, pharmacokinetics, and antimalarial activity of a tablet formulation of MMV390048. Methods A 2-part, phase 1 trial was conducted in healthy adults. Part 1 was a double-blind, randomized, placebo-controlled, single ascending dose study consisting of 3 cohorts (40, 80, 120 mg MMV390048). Part 2 was an open-label volunteer infection study using the Plasmodium falciparum induced blood-stage malaria model consisting of 2 cohorts (40 mg and 80 mg MMV390048). Results Twenty four subjects were enrolled in part 1 (n = 8 per cohort, randomized 3:1 MMV390048:placebo) and 15 subjects were enrolled in part 2 (40 mg [n = 7] and 80 mg [n = 8] cohorts). One subject was withdrawn from part 2 (80 mg cohort) before dosing and was not included in analyses. No serious or severe adverse events were attributed to MMV390048. The rate of parasite clearance was greater in subjects administered 80 mg compared to those administered 40 mg (clearance half-life 5.5 hours [95% confidence interval {CI}, 5.2–6.0 hours] vs 6.4 hours [95% CI, 6.0–6.9 hours]; P = .005). Pharmacokinetic/pharmacodynamic modeling estimated a minimum inhibitory concentration of 83 ng/mL and a minimal parasiticidal concentration that would achieve 90% of the maximum effect of 238 ng/mL, and predicted that a single 120-mg dose would achieve an adequate clinical and parasitological response with 92% certainty. Conclusions The safety, pharmacokinetics, and pharmacodynamics of MMV390048 support its further development as a partner drug of a single-dose combination therapy for malaria. Clinical Trials Registration NCT02783820 (part 1); NCT02783833 (part 2)., MMV390048 is a promising new antimalarial compound in clinical development. We characterized the safety, pharmacokinetics, and antimalarial activity of MMV390048 in healthy adults. The results support the development of MMV390048 as a partner drug of a single-dose combination malaria therapy.

Plasmodium malariae is considered a minor malaria parasite, although its global disease burden is underappreciated. The aim of this study was to develop an induced blood-stage malaria (IBSM) model of P. malariae to study parasite biology, diagnostic assays, and treatment.This clinical trial involved 2 healthy subjects who were intravenously inoculated with cryopreserved P. malariae-infected erythrocytes. Subjects were treated with artemether-lumefantrine after development of clinical symptoms. Prior to antimalarial therapy, mosquito-feeding assays were performed to investigate transmission, and blood samples were collected for rapid diagnostic testing and parasite transcription profiling. Serial blood samples were collected for biomarker analysis.Both subjects experienced symptoms and signs typical of early malaria. Parasitemia was detected 7 days after inoculation, and parasite concentrations increased until antimalarial treatment was initiated 25 and 21 days after inoculation for subjects 1 and 2 respectively (peak parasitemia levels, 174 182 and 50 291 parasites/mL, respectively). The parasite clearance half-life following artemether-lumefantrine treatment was 6.7 hours. Mosquito transmission was observed for 1 subject, while in vivo parasite transcription and biomarkers were successfully profiled.An IBSM model of P. malariae has been successfully developed and may be used to study the biology of, diagnostic testing for, and treatment of this neglected malaria species.ACTRN12617000048381.

Summary Background (+)-SJ000557733 (SJ733) is a novel, orally bioavailable inhibitor of Plasmodium falciparum ATP4. In this first-in-human and induced blood-stage malaria phase 1a/b trial, we investigated the safety, tolerability, pharmacokinetics, and antimalarial activity of SJ733 in humans. Methods The phase 1a was a single-centre, dose-escalation, first-in-human study of SJ733 allowing modifications to dose increments and dose-cohort size on the basis of safety and pharmacokinetic results. The phase 1a took place at St Jude Children's Research Hospital and at the University of Tennessee Clinical Research Center (Memphis, TN, USA). Enrolment in more than one non-consecutive dose cohort was allowed with at least 14 days required between doses. Participants were fasted in seven dose cohorts and fed in one 600 mg dose cohort. Single ascending doses of SJ733 (75, 150, 300, 600, 900, or 1200 mg) were administered to participants, who were followed up for 14 days after SJ733 dosing. Phase 1a primary endpoints were safety, tolerability, and pharmacokinetics of SJ733, and identification of an SJ733 dose to test in the induced blood-stage malaria model. The phase 1b was a single-centre, open-label, volunteer infection study using the induced blood-stage malaria model in which fasted participants were intravenously infected with blood-stage P falciparum and subsequently treated with a single dose of SJ733. Phase 1b took place at Q-Pharm (Herston, QLD, Australia) and was initiated only after phase 1a showed that exposure exceeding the threshold minimum exposure could be safely achieved in humans. Participants were inoculated on day 0 with P falciparum-infected human erythrocytes (around 2800 parasites in the 150 mg dose cohort and around 2300 parasites in the 600 mg dose cohort), and parasitaemia was monitored before malaria inoculation, after inoculation, immediately before SJ733 dosing, and then post-dose. Participants were treated with SJ733 within 24 h of reaching 5000 parasites per mL or at a clinical score higher than 6. Phase 1b primary endpoints were calculation of a parasite reduction ratio (PRR48) and parasite clearance half-life, and safety and tolerability of SJ733 (incidence, severity, and drug-relatedness of adverse events). In both phases of the trial, SJ733 hydrochloride salt was formulated as a powder blend in capsules containing 75 mg or 300 mg for oral administration. Healthy men and women (of non-childbearing potential) aged 18–55 years were eligible for both studies. Both studies are registered with ClinicalTrials.gov ( NCT02661373 for the phase 1a and NCT02867059 for the phase 1b). Findings In the phase 1a, 23 healthy participants were enrolled and received one to three non-consecutive doses of SJ733 between March 14 and Dec 7, 2016. SJ733 was safe and well tolerated at all doses and in fasted and fed conditions. 119 adverse events were recorded: 54 (45%) were unrelated, 63 (53%) unlikely to be related, and two (2%) possibly related to SJ733. In the phase 1b, 17 malaria-naive, healthy participants were enrolled. Seven participants in the 150 mg dose cohort were inoculated and dosed with SJ733. Eight participants in the 600 mg dose cohort were inoculated, but two participants could not be dosed with SJ733. Two additional participants were subsequently inoculated and dosed with SJ733. SJ733 exposure increased proportional to the dose through to the 600 mg dose, then was saturable at higher doses. Fasted participants receiving 600 mg exceeded the target area under the concentration curve extrapolated to infinity (AUC0–∞) of 13 000 μg × h/L (median AUC0–∞ 24 283 [IQR 16 135–31 311] μg × h/L, median terminal half-life 17·4 h [IQR 16·1–24·0], and median timepoint at which peak plasma concentration is reached 1·0 h [0·6–1·3]), and this dose was tested in the phase 1b. All 15 participants dosed with SJ733 had at least one adverse event. Of the 172 adverse events recorded, 128 (74%) were mild. The only adverse event attributed to SJ733 was mild bilateral foot paraesthesia that lasted 3·75 h and resolved spontaneously. The most common adverse events were related to malaria. Based on parasite clearance half-life, the derived log10 PRR48 and corresponding parasite clearance half-lives were 2·2 (95% CI 2·0–2·5) and 6·47 h (95% CI 5·88–7·18) for 150 mg, and 4·1 (3·7–4·4) and 3·56 h (3·29–3·88) for 600 mg. Interpretation The favourable pharmacokinetic, tolerability, and safety profile of SJ733, and rapid antiparasitic effect support its development as a fast-acting component of combination antimalarial therapy. Funding Global Health Innovative Technology Fund, Medicines for Malaria Venture, and the American Lebanese Syrian Associated Charities.

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., John Woodford and co-authors use positron emission tomography/magnetic resonance imaging (PET/MRI) to describe unique splenic morphology and metabolism in early P. vivax infection., Author summary Why was this study done? In contrast to Plasmodium falciparum, blood-stage Plasmodium vivax is not traditionally thought to accumulate outside of the circulating blood compartment. Emerging data suggest that a hidden compartment of P. vivax may exist outside of circulation, in reticulocyte (very young red blood cells)-containing organs. The presence of a hidden compartment affects our understanding of the basic biology and pathology of this common parasite and may have implications when developing antimalarial treatments. Studying the accumulation of malaria parasites is extremely challenging in vivo and has historically been limited to late stage disease and postmortem studies. What did the researchers do and find? We performed whole body magnetic resonance imaging (MRI) and positron emission tomography (PET) in individuals undergoing experimental malaria infection to identify changes in organ morphology and glucose metabolism following infection. Splenic uptake of radiolabeled glucose increased following P. vivax and P. falciparum infection and was more pronounced in the P. vivax group. Glucose uptake in the liver and bone marrow was not increased following infection with either P. vivax or P. falciparum. What do these findings mean? Increased splenic glucose metabolism is present in the early stages of infection with both P. vivax and P. falciparum and is more pronounced in P. vivax, consistent with other emerging evidence of a greater predilection for the spleen in P. vivax than P. falciparum. Functional medical imaging may be a useful tool to study biological processes in experimental malaria infection.

Liver dysfunction has long been recognized as a clinical feature of malaria. We have observed delayed elevation in the transaminase portion of liver function tests (LFTs) after treatment in some participants undergoing induced blood stage malaria infection. We sought to determine whether similar LFT elevations occur after naturally acquired infection. We performed a retrospective audit of confirmed cases of Plasmodium falciparum and Plasmodium vivax in Queensland, Australia, from 2006 to 2016. All LFT results from malaria diagnosis until 28 days after diagnosis were collected with demographic and clinical information to describe longitudinal changes. The timing of peak LFT elevations was classified as early (0–3 days), delayed (4–11 days), or late (12–28 days) with respect to the day of diagnosis. Among 861 cases with LFT evaluated, an elevated bilirubin level was identified in 12.4% (N = 107/861), whereas elevated alanine transaminase (ALT) and aspartate transaminase levels were observed in 15.1% (N = 130/861) and 14.8% (N = 127/861) of cases, respectively. All peak bilirubin results occurred in the early period, whereas ALT elevations were biphasic, with elevations in the early and delayed periods, with 35.4% (N = 46/130) of cases delayed. Univariate and paired stepwise logistic regression analyses were performed to investigate factors associated with the incidence and timing of transaminase elevation. A raised ALT level at diagnosis was strongly associated with the timing of transaminase elevation. No other demographic, parasitic, or treatment factors were associated. Liver function test abnormalities are likely an inherent although variable aspect of human malaria, and individual-specific factors may confer susceptibility to hepatocyte injury.

Composites consisting of a conjugated linseed or soybean oil-based thermoset reinforced with wood flour and wood fibers have been prepared by free radical polymerization. The thermoset resin consists of a copolymer of conjugated linseed oil (CLO) or conjugated soybean oil (CSO), n-butyl methacrylate (BMA), divinylbenzene (DVB), and maleic anhydride (MA). The composites were cured at 180°C and 600 psi and postcured for 2 h at 200°C under atmospheric pressure. The effect of varying filler load, time of cure, filler particle size, origin of the fillers, and resin composition has been assessed by means of tensile tests, DMA, TGA, Soxhlet extraction followed by 1H-NMR spectroscopic analysis of the extracts, and DSC. The best processing conditions have been established for the pine wood flour composites. It has been observed that the addition of MA to the resin composition improves the filler-resin interaction. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Stringent emission standards are driving the development of diesel-fuel injection concepts to mitigate in-cylinder formation of particulates. While research has demonstrated significant reduction in particulate formation using micro-orifice technology, implementation requires development of industrial processes to fabricate micro-orifices with diameters as low as 50 gmm and with large length-to-diameter ratios. This paper reviews the different processes being pursued to fabricate micro-orifices and the advanced techniques applied to characterize the performance of micro-orifices. The latter include the use of phase-contrast x-ray imaging of electroless nickel-plated, micro-orifices and laser imaging of fuel sprays at elevated pressures. The experimental results demonstrate an industrially viable process to create small uniform orifices that improve spray formation for fuel injection.

A detailed study of the top surface (similar to 2 nm) of a near frictionless carbon film has revealed new information with respect to the sp(3) fraction. Previous work on near frictionless carbon films made at Argonne had shown a large fraction of sp(2)-hybridized carbon in the bulk of the film. However, in this study of the surface, the majority of the carbon was found to be sp(3). In addition we compared and contrasted the behavior of the films after mechanical abrasion and Ar+ etching. The study also revealed that oxygen on untreated samples was rapidly reduced by etching or heating or mechanical abrasions this finding was corroborated by an angle-resolved study, where different depths of the sample were probed. It was also found that the traction of sp(3) carbon decreased linearly with depth, falling in one film from similar to 90% sp(3) to similar to 80% sp(3) in the top 2 nm. (c) 2006 Elsevier B.V. All rights reserved.

The rocks of the north-eastern Strangways Range, central Australia, display a broad range of chemical types and have been subjected to at least four periods of metamorphic activity.Of the six rock sequences delineated five are dominated by felsic rocks and include meta-tuffaceous and pre-metamorphic intrusive igneous rocks; the sixth sequence contains an extensive occurrence of interbedded calc-silicates and marbles. The mafic rocks, accompanied by rare, interlayered ultramafic types lacking plagioclase, are characterised by the ubiquitous presence of hornblende and by low SiO2, K2O, Na2O and a high MgO/FeO ratio. The presence of aluminous rocks, particularly in the Western Zone Granulites sequence, has facilitated the development of the rare minerals sapphirine, hogbomite, kornerupine and yoderite (?) and the unusual mineral assemblages sillimanite - orthopyroxene and kyanite - cordierite.Repeated metasomatic addition of K, Rb and Ba has extensively modified rock chemistry, particularly of the felsic rocks. Metamorphic depletion of Rb and high K/Rb ratios have not been observed. In all rock types anomalously low contents of Sr are attributed to low Sr levels in the mantle underlying the Strangways Range, at least prior to early Proterozoic times. Low Sr appears to be a feature typical of a number of other metamorphic terrains in the Australian Shield. Unusually low Sr in the marbles (80 ppm) is attributed to diagenetic and metamorphic depletion of initially low levels at sedimentation.Four metamorphic episodes, M1 - M2 - M3 - M4, have been petrologically categorised, geochronologically delineated and the stable mineral assemblages geochemically contrasted.The first recognisable event. M1, is a granulite metamorphism dated elsewhere in the Strangways Range as 1860 ± 60 m.y., and is characterised by the stability of hornblende and cordierite. High KD values for the distribution of Fe and Mg between orthopyroxene and clinopyroxene in mafic granulites, similar Alⅳ and Alⅵ levels in orthopyroxene from mafic granulites, Fe/Mg distribution between garnet and phlogopite, the Mg content of calcite and the stable mineral assemblages indicate pressure-temperature conditions of 8.5 to 9 kb and 700°-750°C.The second recorded event, M2, is another granulite metamorphism, dated as 1470 ± 70 m.y., in which three phases are recognised. The first phase, characterised by the instability of hornblende and its replacement by pyroxene, and the replacement of cordierite by sillimanite, orthopyroxene and quartz represents pressure-temperature conditions of ll.5 kb and 900°C. The second phase of M2 is reflected in the development of garnet in pyroxene assemblages and the stability of hornblende. Pressure-temperature conditions of approximately 9 kb and 850°C prevailed. The third phase is characterised by upper amphibolite facies conditions reflected in the development of amphibolite facies minerals in many of the M2-recrystallised felsic rocks.The M3 event, dated as 700-800 m.y., caused partial to complete argon degassing of many of the M1 and M2 micas and hornblendes but only very limited mineral reconstitution.The M4 event was a structurally-controlled retrogressive event dated as 327 m.y. to 352 m.y. Metamorphic conditions were of the order of 6 kb and 600°C.The study has illustrated the rewards of a unified approach to unravel the geological history of a polymetamorphic terrain.

The tribological characteristics of a diamondlike carbon (DLC) film deposited on high-speed steel were investigated systematically by using a ball-on-flat reciprocating tribometer over a range of temperatures (from −40° to 20°C). The results indicated that the temperature dependence of the DLC film's tribological behavior was associated with the counterpart material. DLC presented favorable tribological behavior while sliding on itself. However, when a steel ball slides against the DLC film, there is evidence that the heat generated has a significant impact on friction and wear. Microanalysis of wear tracks on the films showed that multiple wear mechanisms took place during testing. At higher temperatures, material transfer dominated the wear behavior, while fatigue-induced microcracking was the predominant wear mechanism at low temperatures. Raman analysis indicated that the DLC film was mechanically worn rather than removed by tribochemical interactions between the friction pairs.

(2004). Bill Cosby, Education, and the Lumpenizing of the Contemporary Black World. The Black Scholar: Vol. 34, Black Education, pp. 21-26.

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.

Million-cycle reciprocating wear tests have been carried out to determine the ultimate wear lifetime of near-frictionless carbon (NFC) coatings applied to production fuel-injector tips. Wear tests were performed in existing and reformulated gasolines as part of a study to improve fuel systems for spark-ignited, direct-injected (SIDI) engines. Ball-on-three-disc (BOTD) tests were performed to determine the lubricity of the gasolines, and the wear surfaces were analyzed using Raman spectroscopy. NFC coatings reduced friction and total wear by up to 48% and 39%, respectively. No evidence was seen of coating graphitization, the formation of transfer films from the coatings, or the presence of chemical protective films originating from the gasolines.

The suitability of diamond-like carbon (DLC) coatings for reduction of friction and wear in spark-ignited, direct-injected fuel systems has been investigated. Three commercially available DLC coatings have been compared to near-frictionless carbon (NFC) coatings and to uncoated metal in standardized lubricity tests and custom wear tests intended to simulate the fuel system environment. The coatings were applied to both laboratory balls and flats and to production fuel injector tips. These coatings provided improvements in friction and wear over uncoated surfaces, with the greatest improvements found in parts coated with NFC.

In this work the tribological behavior of hard carbon films on steel substrates has been studied under moderately high contact stress conditions. Diamond-like carbon (DLC) coatings of 1 μm thickness were deposited by a plasma-enhanced chemical vapor deposition (PECVD) process on hardened substrates made from 4140 alloy steel. The coated flat specimens were tested in an oscillatory pin-on-disk configuration in contact with either uncoated or carbon-coated hardened steel balls. Peak Hertzian contact pressures ranged from about 300 to 500 MPa and mean sliding velocity was 50 mm/s. In some tests, the specimens were lubricated with 10W-30 motor oil. It was found that wear of the carbon coatings was approximately linearly proportional to contact force. For unlubricated tests, wear rates of the coated specimens were about 200 times less than rates of wear of uncoated steel specimens for the same contact force. The contacting steel ball (uncoated) showed even greater wear reduction (more than 3 orders of magnitude) when tested against coated substrates. Friction coefficients were four to five times lower for coated specimens. Coating the ball as well as the flat resulted in a further reduction (about 50%) in wear of both ball and flat. Friction and wear reduction brought about by carbon coating in lubricated tests was less than for unlubricated specimens.

(1999). Pilots Without Wings—A Critique of the PBS Documentary, The Black Press: Soldiers Without Swords. The Black Scholar: Vol. 29, Black Women Writers, pp. 68-72.

A high-density top-surface layer of approximately 30 A was found in a form of diamondlike carbon, “near-frictionless carbon,” developed at Argonne National Laboratory. Three diamondlike-carbon films were prepared by plasma-enhanced chemical vapor deposition with different hydrogen-to-methane ratios in the plasma. Complementary films were prepared with deuterated methane and deuterium, in the same ratios. Results from neutron relectivity experiments are presented, along with model comparisons, and a hypothesis is postulated.

The strategy originated in the Reagan regime, and the first target was affirmative action. Unlike their Democratic Party counterparts, the Republican reactionaries are able to conceive of long-term objectives and to move toward them with deliberate speed. They appreciate the years of double-talk and media brainwashing needed to turn a pivotal section of the white populace to the right. The affirmative action cases arise from

Rabies is a rapidly progressive and fatal encephalitis caused by a lyssavirus in the family Rhabdoviridae. Lyssaviruses are RNA viruses that most commonly exhibit intraspecies transmission; however, the rabies virus commonly spills into other species. The disease is transmitted through introduction of infected saliva into the body via bites, scratches, mucosal exposure, or rarely through inhalation of aerosolized saliva in enclosed spaces (caves with infected bat colonies). Common vectors include medium to large terrestrial mammals and bats. Globally, the canine variant of rabies virus is the leading cause of human disease. The majority of human cases occur in Asia (95%) and of these,99% are transmitted through contact with infected dogs. Without appropriate vaccination and population control, feral animals contribute to the maintenance of sylvatic rabies cycles in local wildlife and increased rabies risk to humans. The purpose of this paper is to be a comprehensive resource regarding the rabies virus and critical factors to consider while developing courses of action for control programs; the intended audience includes working groups and individuals who deal with feral animal control. This document is an information resource only and is not intended to provide specific courses of action for program implementation. This paper provides a comprehensive overview of the epidemiology, clinical signs, and etiology of rabies, as well as diagnostic modalities and current control measures and techniques. A comprehensive understanding of the virus and the environment in which it survives is essential to carrying out appropriate assessments and developing improved control methods to be used in Joint Operations Areas (JOA).

Richard Wright were alive today, he would point to the end of the Cold War as posing the gravest threat to the AfricanAmerican struggle for justice and equality. That is perhaps the most important lesson that Wright sends to us from the grave, as it were, through the recently published Conversations With Richard Wright (University Press of Mississippi, Jackson, 1993, K. Kinnamon and M. Fabre, editors). The book is aptly named. The collection of 63 pieces spans 22 years, from 1938, when the novelist, then just 30 years old, took front stage on the world literary scene, till 1960, the year of his death in France, his adopted homeland. The numerous conversations over