The importance of zooplankton‐protozoan trophic couplings in Lake Michigan

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/109824/1/lno19913671335.pd

Diatom succession in an urban reservoir system

A 43 cm by 5 cm diameter sediment core sample was obtained from Ford Lake reservoir in Washtenaw County, Michigan, and sectioned at 1 cm intervals. The purpose of this study was to determine whether diatom communities in this reservoir have undergone quantifiable changes in abundance and composition since its creation. Thirty-one cm of this core appeared to represent material deposited since the creation of the reservoir based on changes in diatom abundance, the physical composition of the sediment and the change in biogenic SiO 2 concentration. Fortyseven species of diatoms were identified total concentrations of diatom remains varied from 1×10 4 g -1 to 1×10 7 g -1 . Prior to the establishment of the reservoir, the diatom flora was dominated by benthic taxa. Benthic diatoms were numerous throughout the entire core, but eutrophic taxa (e.g., Aulacoseira italica, Aulacoseira granulata, Stephanodiscus niagarae, Fragilaria crotonensis ) dominated much of the core after the reservoir's creation. Total diatom density increased about tenfold in the about the first 10–15 years after the reservoir's creation before declining markedly.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/43076/1/10933_2004_Article_BF00213043.pd

Structure, Dynamics, and Phase Transitions in the Fullerene Derivatives C_{60}O and C_{61}H_{2}

The effect of perturbing the icosohedral symmetry of C60 by the addition of the side groups -O and -CH2 upon orientational order-disorder and glass transitions in solid C60 has been studied by a combination of high-resolution capacitance dilatometry and single-crystal x-ray and powder inelastic neutron scattering. Both fullerene derivatives C60O (epoxide) and C61H2 (6,5-annulene) are shown to undergo a sequence of transitions similar to that found in pure C60, i.e., a first-order orientational ordering transition just below room temperature followed by an orientational glass transition at lower temperatures. Although the exact origin of the glass transition in C61H2 is unclear, the glass transition in C60O has the same origin as that in C60, with a significantly higher degree of order due to a larger energy difference between pentagon and hexagon orientations. The dilatometric data at the glass transition indicate that, in contrast to C60, the ground-state orientation of both C60O and C61H2 molecules is that with the smallest volume, also demonstrating a significant influence of the side groups upon the details of the structure. A possible explanation of these differences in terms of steric effects is proposed

Mannose Binding Lectin Is Required for Alphavirus-Induced Arthritis/Myositis

Mosquito-borne alphaviruses such as chikungunya virus and Ross River virus (RRV) are emerging pathogens capable of causing large-scale epidemics of virus-induced arthritis and myositis. The pathology of RRV-induced disease in both humans and mice is associated with induction of the host inflammatory response within the muscle and joints, and prior studies have demonstrated that the host complement system contributes to development of disease. In this study, we have used a mouse model of RRV-induced disease to identify and characterize which complement activation pathways mediate disease progression after infection, and we have identified the mannose binding lectin (MBL) pathway, but not the classical or alternative complement activation pathways, as essential for development of RRV-induced disease. MBL deposition was enhanced in RRV infected muscle tissue from wild type mice and RRV infected MBL deficient mice exhibited reduced disease, tissue damage, and complement deposition compared to wild-type mice. In contrast, mice deficient for key components of the classical or alternative complement activation pathways still developed severe RRV-induced disease. Further characterization of MBL deficient mice demonstrated that similar to C3−/− mice, viral replication and inflammatory cell recruitment were equivalent to wild type animals, suggesting that RRV-mediated induction of complement dependent immune pathology is largely MBL dependent. Consistent with these findings, human patients diagnosed with RRV disease had elevated serum MBL levels compared to healthy controls, and MBL levels in the serum and synovial fluid correlated with severity of disease. These findings demonstrate a role for MBL in promoting RRV-induced disease in both mice and humans and suggest that the MBL pathway of complement activation may be an effective target for therapeutic intervention for humans suffering from RRV-induced arthritis and myositis

Adherence to standard treatment guidelines among prescribers in primary healthcare facilities in the Dodoma region of Tanzania

Background Tanzania's primary healthcare system suffers from a scarcity of financial and human resources that impedes its effectiveness to deliver dependable and uniform quality healthcare. Adherence to standard treatment guidelines (STG) can help provide more consistent and correct diagnoses and treatments and limit the irrational use of medicines and the negative health consequences that can occur as a result. The purpose of this study was to investigate prescribers' adherence of their diagnoses and respective treatments to national STG and to identify potential areas for planning interventions. Methods A cross-sectional study on prescribers' adherence to diagnosis and treatment, according to national STG, was conducted in 2012 in public primary healthcare facilities (HCF) in the Dodoma region of Tanzania. Information on 2886 patients was collected, prospectively and retrospectively, from 120 HCF across the Dodoma region using a structured questionnaire. Twenty-five broadly defined main illness groups were recorded and the nine most prevalent and relevant conditions were statistically analysed in detail. Results Diagnoses and related treatments were recorded and analysed in 2872 cases. The nine most prevalent conditions were upper respiratory tract infections (25%), malaria (18%), diarrhoea (9.9%), pneumonia (6.1%), skin problems (5.8%), gastrointestinal diagnoses (5%), urinary tract infections (4%), worm infestations (3.6%) and eye problems (2.1%). Only 1.8% of all diagnoses were non-communicable diseases. The proportion of prescribers' primary diagnoses that completely adhered to national STG was 599 (29.9%), those that partially adhered totalled 775 (38.7%), wrong medication was given in 621 cases (30.9%) and no diagnosis or medication was given in nine cases (0.5%). Sixty-one percent of all patients received an antibiotic regardless of the diagnoses. Complete adherence was highest when worms were diagnosed and lowest for diarrhoea. The proportion of cases that did not adhere to STG was highest with patients with skin problems and lowest for malaria. Conclusion Prescribers' general adherence to national STG in primary HCF in the public sector in Dodoma region is sub-optimal. The reasons are multifaceted and focused attention, directed at improving prescribing and pharmacotherapy, is required with a view of improving patient care and health outcomes

Faisabilité et spécificités de l'ASL-EEG simultané à 3T

National audienc