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Capacity investigation of brine-bearing sands of the Frio Formation for geologic sequestration of CO2
The capacity of fluvial brine-bearing formations to sequester CO2 is investigated using numerical simulations of CO2 injection and storage. Capacity is defined as the volume fraction of the subsurface available for CO2 storage and is conceptualized as a product of factors that account for two-phase flow and transport processes, formation geometry, formation heterogeneity, and formation porosity. The space and time domains used to define capacity must be chosen with care to obtain meaningful results, especially when comparing different authors’ work. Physical factors that impact capacity include permeability anisotropy and relative permeability to CO2, brine/CO2 density and viscosity ratios, the shape of the trapping structure, formation porosity and the presence of low permeability layering.National Energy Technology LaboratoryBureau of Economic Geolog
A temperate palaeodiversity peak in Mesozoic dinosaurs and evidence for Late Cretaceous geographical partitioning
Aim  Modern biodiversity peaks in the tropics and declines poleward, a pattern that is potentially driven by climate. Although this latitudinal biodiversity gradient (LBG) also characterizes the marine invertebrate fossil record, distributions of ancient terrestrial faunas are poorly understood. This study utilizes data on the dinosaur fossil record to examine spatial patterns in terrestrial biodiversity throughout the Mesozoic.\ud
Location  We compiled data on fossil occurrences across the globe.\ud
Methods  We compiled a comprehensive dataset of Mesozoic dinosaur genera (738), including birds. Following the utilization of sampling standardization techniques to mediate for the uneven sampling of the fossil record, we constructed latitudinal patterns of biodiversity from this dataset.\ud
Results  The dominant group of Mesozoic terrestrial vertebrates did not conform to the modern LBG. Instead, dinosaur diversity was highest at temperate palaeolatitudes throughout the 160 million year span of dinosaurian evolutionary history. Latitudinal diversity correlates strongly with the distribution of land area. Late Cretaceous sauropods and ornithischians exhibit disparate LBGs.\ud
Main conclusions  The continuity of the palaeotemperate peak in dinosaur diversity indicates a diminished role for climate on the Mesozoic LBG; instead, dinosaur diversity may have been driven by the amount of land area among latitudinal belts. There is no evidence that the tropics acted as a cradle for dinosaur diversity. Geographical partitioning among major clades of herbivorous dinosaurs in the Late Cretaceous may result from the advanced stages of continental fragmentation and/or differing responses to increasing latitudinal climatic zonation. Our results suggest that the modern-day LBG on land was only established 30 million years ago, following a significant post-Eocene recalibration, potentially related to increased seasonality
Antigen depot is not required for alum adjuvanticity
Alum adjuvants have been in continuous clinical use for more than 80 yr. While the prevailing theory has been that depot formation and the associated slow release of antigen and/or inflammation are responsible for alum enhancement of antigen presentation and subsequent T- and B-cell responses, this has never been formally proven. To examine antigen persistence, we used the chimeric fluorescent protein EαGFP, which allows assessment of antigen presentation in situ, using the Y-Ae antibody. We demonstrate that alum and/or CpG adjuvants induced similar uptake of antigen, and in all cases, GFP signal did not persist beyond 24 h in draining lymph node antigen-presenting cells. Antigen presentation was first detectable on B cells within 6–12 h of antigen administration, followed by conventional dendritic cells (DCs) at 12–24 h, then finally plasmacytoid DCs at 48 h or later. Again, alum and/or CpG adjuvants did not have an effect on the magnitude or sequence of this response; furthermore, they induced similar antigen-specific T-cell activation in vivo. Notably, removal of the injection site and associated alum depot, as early as 2 h after administration, had no appreciable effect on antigen-specific T- and B-cell responses. This study clearly rules out a role for depot formation in alum adjuvant activity
A novel cellular pathway of antigen presentation and CD4 T cell activation in vivo
Dendritic cell activation of CD4 T cells in the lymph node draining a site of infection or vaccination is widely considered the central event in initiating adaptive immunity. The accepted dogma is that this occurs by stimulating local activation and antigen acquisition by dendritic cells, with subsequent lymph node migration, however the generalizability of this mechanism is unclear. Here we show that in some circumstances antigen can bypass the injection site inflammatory response, draining freely and rapidly to the lymph nodes where it interacts with subcapsular sinus (SCS) macrophages resulting in their death. Debris from these dying SCS macrophages is internalized by monocytes recruited from the circulation. This coordinated response leads to antigen presentation by monocytes and interactions with naïve CD4 T cells that can drive the initiation of T cell and B cell responses. These studies demonstrate an entirely novel pathway leading to initiation of adaptive immune responses in vivo
Asymmetric cationic phosphines: synthesis, coordination chemistry, and reactivity
A single enantiomer of a cationic phosphine, [α-CgPAmHMe]BF4 has been synthesized and coordinated to Rh(I), Au(I), Ag(I), Cu(I), and Pt(0). Analysis of pertinent empirical data reveals the ligand to be highly electron-withdrawing due to the cationic amidinium group directly bound to the phosphorus. The N−P bond connecting the amidinium and the phosphacycle is susceptible to attack by nucleophiles (H2O, OH−) when coordinated leading to bond rupture and release of the neutral amidine group. These fortuitous observations suggest that [α-CgPAmHMe]BF4 may be a very useful synthon for the production of novel asymmetric phosphines
Characterisation of the vaginal microflora of human immunodeficiency virus (HIV) positive and negative women in a sub-urban population of Kenya
Lactobacilli predominate normal vaginal microflora and are important in maintenance of vaginal health. The current study set out to identify and compare culture isolates of vaginal microflora of human immunodeficiency virus (HIV) positive (HIV+ ) and HIV negative (HIV- ) women at different phases during menstrual cycle from a sub-urban population of Kenya. Seventy four (74) women, 41 HIV+ and 33 HIV- , followed up two consecutive menstrual cycles, had high vaginal swabs taken to prepare Gram stains for six visits and anaerobic cultures for four. All 751 isolates identified by t-DNA polymerase chain reaction (PCR) belong to 51 species. Species cultured more frequently in HIV+ participants were: Lactobacillus jensenii (p=0.01), Lactobacillus iners (p=0.02), Gardnerella vaginalis (p=0.01) and Peptoniphilus lacrimalis (p=0.01). Species cultured more frequently in HIV- women were Dialister micraerophilus (p=0.02) and Streptococcus agalactiae (p=0.04). Lactobacillus predominating both groups were Lactobacilli crispatus, L. jensenii, L. iners and Lactobacilli vaginalis. Bacterial vaginosis (BV) was equally high in HIV+ and HIV- women. Lactobacillus and BV-associated species were cultured more frequently in HIV+ women. Minor species differences were found. Predominant Lactobacillus in culture were L. crispatus, L. iners, L. jensenii and L. vaginalis. These women had lower concentrations of lactobacilli in vaginal microflora than observed in previous studies of Caucasian women
Modelling studies of the hazards posed by liquid hydrogen use in civil aviation
As part of the ENABLEH2 project, modelling studies have been carried out to examine liquid hydrogen release and dispersion behaviour for different LH2 aircraft and airport infrastructure leak/spill accident scenarios. The FLACS CFD model has been used to simulate the potential hazard effects following an accidental LH2 leak, including the extent of the flammable LH2 clouds formed, magnitude of explosion overpressures and pool fire radiation hazards. A comparison has also been made between the relative hazard consequences of using LH2 with conventional Jet A/A-1 fuel. The results indicate that in the event of accidental fuel leak/spill LH2 has some safety advantages over Jet A/A-1 but will also introduce additional hazards not found with Jet A/A-1 that will need to be carefully managed and mitigated against.European Union funding: 76924
Tumour inflammatory infiltrate predicts survival following curative resection for node-negative colorectal cancer
<b>Background</b>: A pronounced tumour inflammatory infiltrate is known to confer a good outcome in colorectal cancer. Klintrup and colleagues reported a structured assessment of the inflammatory reaction at the invasive margin scoring low grade or high grade. The aim of the present study was to examine the prognostic value of tumour inflammatory infiltrate in node-negative colorectal cancer.
<b>Methods</b>: Two hundred patients had undergone surgery for node-negative colorectal cancer between 1997 and 2004. Specimens were scored with Jass’ and Klintrup’s criteria for peritumoural infiltrate. Pathological data were taken from the reports at that time.
<b>Results</b>: Low-grade inflammatory infiltrate assessed using Klintrup’s criteria was an independent prognostic factor in node-negative disease. In patients with a low-risk Petersen Index (n = 179), low-grade infiltrate carried a threefold increased risk of cancer death. Low-grade infiltrate was related to increasing T stage and an infiltrating margin.
<b>Conclusion</b>: Assessment of inflammatory infiltrate using Klintrup’s criteria provides independent prognostic information on node-negative colorectal cancer. A high-grade local inflammatory response may represent effective host immune responses impeding tumour growth
Welcoming neighbour or inhospitable host? Selective second metal binding in 5- and 6-phospha-substituted Bpy ligands
The controlled formation of mixed-metal bimetallics was realised through use of a fac-[Re(CO)3(N,N′-bpy-P)Cl] complex bearing an exogenous 2,4,6-trioxa-1,3,5,7-tetramethyl-8-phosphaadamantane donor at the 5-position of the bpy. The introduction of gold, silver, and rhodium with appropriate secondary ligands was readily achieved from established starting materials. Restricted rotation about the C(bpy)-P bond was observed in several of the bimetallic complexes and correlated with the relative steric bulk of the second metal moiety. Related chemistry with the 6-substituted derivative proved more limited in scope with only the bimetallic Re/Au complex being isolated
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