63 research outputs found
Application of Split Desktop Image Analysis and Kuz-Ram Empirical Model for Evaluation of Blast Fragmentation Efficiency in a Typical Granite Quarry
Evaluation of fragmentation efficiency is an integral aspect of blasting operation. This study therefore assesses the efficiency of fragmentation size at Eminent granite quarry, Ibadan, Nigeria using Split Desktop software and Kuz-Ram empirical model. Five muckpiles of blasted rocks with the same blast design were analysed. The muckpile images were captured using smart high precision digital camera and uploaded into computer for Split Desktop analysis. The results of the fragment size distribution obtained from Kuz-Ram vary slightly with that of the Split Desktop but follow similar trend. The average values of F80 and F90 from the Split Desktop image analysis were 90.96 cm and 98.24 cm respectively. The Kuz-Ram model values for F80 and F90 were 88.52 cm and 92.95 cm respectively. The results of the Split Desktop were compared to the results obtained from the Kuz-Ram experiential model. The findings showed that the results obtained from Kuz-Ram empirical model were in conformity with the results from the Split Desktop software based on empirical relationship. Hence, the model is good for preliminary evaluation of blast design.
Keywords: Blasting, Particle Size Distribution, Split Desktop Software, Muckpile, Fragmentation Indicato
Chemical constituents and anti-inflammatory activity of leaf essential oil of Nigerian grown Chenopodium album L.
Hydrodistilled leaves of Chenopodium album yielded 0.64 % v/w of essential oil. GC and
GC/MS analyses of the oil revealed that the bulk of the oil was constituted by aromatic compounds (60.1 %). The abundant constituents of the oil were: p- cymene (40.9 %), ascaridole (15.5 %), pinane-2-ol (9.9 %), Ξ±-pinene (7.0 %), Ξ²-pinene (6.2 %) and Ξ±-terpineol (6.2 %). The oil displayed strong anti-inflammatory activity against 12-O-tetradecanoylphorbol-13-acetate (TPA) β induced ear edema in mice
Irreducible Hamiltonian BRST analysis of Stueckelberg coupled p-form gauge theories
The irreducible Hamiltonian BRST symmetry for p-form gauge theories with
Stueckelberg coupling is derived. The cornerstone of our approach is
represented by the construction of an irreducible theory that is equivalent
from the point of view of the BRST formalism with the original system. The
equivalence makes permissible the substitution of the BRST quantization of the
reducible model by that of the irreducible theory. Our procedure maintains the
Lorentz covariance of the irreducible path integral.Comment: 29 pages, LaTeX 2.0
Ethylene tetramerization with a highly active and long-lifetime trinuclear diphenylphosphinoamine/Cr(III)/MAO catalyst
Synchronal and cyclic algorithms for fixed point problems and variational inequality problems in Banach spaces
Reactivation of M. tuberculosis Infection in Trans-Membrane Tumour Necrosis Factor Mice
Of those individuals who are infected with M. tuberculosis, 90% do not develop active disease and represents a large reservoir of M. tuberculosis with the potential for reactivation of infection. Sustained TNF expression is required for containment of persistent infection and TNF neutralization leads to tuberculosis reactivation. In this study, we investigated the contribution of soluble TNF (solTNF) and transmembrane TNF (Tm-TNF) in immune responses generated against reactivating tuberculosis. In a chemotherapy induced tuberculosis reactivation model, mice were challenged by aerosol inhalation infection with low dose M. tuberculosis for three weeks to establish infection followed chemotherapeutic treatment for six weeks, after which therapy was terminated and tuberculosis reactivation investigated. We demonstrate that complete absence of TNF results in host susceptibility to M. tuberculosis reactivation in the presence of established mycobacteria-specific adaptive immunity with mice displaying unrestricted bacilli growth and diffused granuloma structures compared to WT control mice. Interestingly, bacterial re-emergence is contained in Tm-TNF mice during the initial phases of tuberculosis reactivation, indicating that Tm-TNF sustains immune pressure as in WT mice. However, Tm-TNF mice show susceptibility to long term M. tuberculosis reactivation associated with uncontrolled influx of leukocytes in the lungs and reduced IL-12p70, IFNΞ³ and IL-10, enlarged granuloma structures, and failure to contain mycobacterial replication relative to WT mice. In conclusion, we demonstrate that both solTNF and Tm-TNF are required for maintaining immune pressure to contain reactivating M. tuberculosis bacilli even after mycobacteria-specific immunity has been established
Phosphodiesterase-4 Inhibition Alters Gene Expression and Improves Isoniazid β Mediated Clearance of Mycobacterium tuberculosis in Rabbit Lungs
Tuberculosis (TB) treatment is hampered by the long duration of antibiotic therapy required to achieve cure. This indolent response has been partly attributed to the ability of subpopulations of less metabolically active Mycobacterium tuberculosis (Mtb) to withstand killing by current anti-TB drugs. We have used immune modulation with a phosphodiesterase-4 (PDE4) inhibitor, CC-3052, that reduces tumor necrosis factor alpha (TNF-Ξ±) production by increasing intracellular cAMP in macrophages, to examine the crosstalk between host and pathogen in rabbits with pulmonary TB during treatment with isoniazid (INH). Based on DNA microarray, changes in host gene expression during CC-3052 treatment of Mtb infected rabbits support a link between PDE4 inhibition and specific down-regulation of the innate immune response. The overall pattern of host gene expression in the lungs of infected rabbits treated with CC-3052, compared to untreated rabbits, was similar to that described in vitro in resting Mtb infected macrophages, suggesting suboptimal macrophage activation. These alterations in host immunity were associated with corresponding down-regulation of a number of Mtb genes that have been associated with a metabolic shift towards dormancy. Moreover, treatment with CC-3052 and INH resulted in reduced expression of those genes associated with the bacterial response to INH. Importantly, CC-3052 treatment of infected rabbits was associated with reduced ability of Mtb to withstand INH killing, shown by improved bacillary clearance, from the lungs of co-treated animals compared to rabbits treated with INH alone. The results of our study suggest that changes in Mtb gene expression, in response to changes in the host immune response, can alter the responsiveness of the bacteria to antimicrobial agents. These findings provide a basis for exploring the potential use of adjunctive immune modulation with PDE4 inhibitors to enhance the efficacy of existing anti-TB treatment
Increasing frailty is associated with higher prevalence and reduced recognition of delirium in older hospitalised inpatients: results of a multi-centre study
Purpose Delirium is a neuropsychiatric disorder delineated by an acute change in cognition, attention, and consciousness. It is common, particularly in older adults, but poorly recognised. Frailty is the accumulation of deficits conferring an increased risk of adverse outcomes. We set out to determine how severity of frailty, as measured using the CFS, affected delirium rates, and recognition in hospitalised older people in the United Kingdom. Methods Adults over 65 years were included in an observational multi-centre audit across UK hospitals, two prospective rounds, and one retrospective note review. Clinical Frailty Scale (CFS), delirium status, and 30-day outcomes were recorded. Results The overall prevalence of delirium was 16.3% (483). Patients with delirium were more frail than patients without delirium (median CFS 6 vs 4). The risk of delirium was greater with increasing frailty [OR 2.9 (1.8β4.6) in CFS 4 vs 1β3; OR 12.4 (6.2β24.5) in CFS 8 vs 1β3]. Higher CFS was associated with reduced recognition of delirium (OR of 0.7 (0.3β1.9) in CFS 4 compared to 0.2 (0.1β0.7) in CFS 8). These risks were both independent of age and dementia. Conclusion We have demonstrated an incremental increase in risk of delirium with increasing frailty. This has important clinical implications, suggesting that frailty may provide a more nuanced measure of vulnerability to delirium and poor outcomes. However, the most frail patients are least likely to have their delirium diagnosed and there is a significant lack of research into the underlying pathophysiology of both of these common geriatric syndromes
Increasing frailty is associated with higher prevalence and reduced recognition of delirium in older hospitalised inpatients: results of a multi-centre study
Purpose:
Delirium is a neuropsychiatric disorder delineated by an acute change in cognition, attention, and consciousness. It is common, particularly in older adults, but poorly recognised. Frailty is the accumulation of deficits conferring an increased risk of adverse outcomes. We set out to determine how severity of frailty, as measured using the CFS, affected delirium rates, and recognition in hospitalised older people in the United Kingdom.
Methods:
Adults over 65 years were included in an observational multi-centre audit across UK hospitals, two prospective rounds, and one retrospective note review. Clinical Frailty Scale (CFS), delirium status, and 30-day outcomes were recorded.
Results:
The overall prevalence of delirium was 16.3% (483). Patients with delirium were more frail than patients without delirium (median CFS 6 vs 4). The risk of delirium was greater with increasing frailty [OR 2.9 (1.8β4.6) in CFS 4 vs 1β3; OR 12.4 (6.2β24.5) in CFS 8 vs 1β3]. Higher CFS was associated with reduced recognition of delirium (OR of 0.7 (0.3β1.9) in CFS 4 compared to 0.2 (0.1β0.7) in CFS 8). These risks were both independent of age and dementia.
Conclusion:
We have demonstrated an incremental increase in risk of delirium with increasing frailty. This has important clinical implications, suggesting that frailty may provide a more nuanced measure of vulnerability to delirium and poor outcomes. However, the most frail patients are least likely to have their delirium diagnosed and there is a significant lack of research into the underlying pathophysiology of both of these common geriatric syndromes
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