1,339 research outputs found

    Development and quantification of a dust reduction program in longwall mining at metropolitan colliery - a case study

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    Harmful respirable dust produced during longwall mining is a major concern for production, safety and the health of workers in the underground coal mining sector both in Australia and globally, Longwall personnel are exposed to harmful dust from multiple dust generation sources including, but not limited to intake entry, belt entry, stageloader/cnisher, shearer, shield advance and dust ingress from falling goal or over pressurisation of the goal the increase in production created from the advancement in longwall equipment, dust loads have significantly increased and this has resulted in a potentially greater exposure level to personnel. Metropolitan Colliery, located at Helensburgli in NSW, Australia, in conjunction with the University of Wollongong, P11/116 Laboratories and EnviroCon, has implemented a dust reduction program Utilising a recently developed Dust Mitigation Efficiency Model to quantify dust loads produced during the cutting cycle. With the quantification of.this benchmark dust load production along with the quantification of installed control efficiencies at independent sources of dust generation, Metropolitan Colliery, with the installation of the latest shearer scrubber technology has successfully reduced the respirable dust levels in excess of 70% of benchmark levels on their operating Iongwali This reduction will have a significant and immediate positive effebt on employees, production and operating costs which will be maintained throughout the life of the mine

    Buying Products from Whom You Know: Personal Connections and Information Asymmetry in Supply Chain Relationships

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    This study investigates the role personal connections play in a crucial element of the supply chain—supplier selection. We find that the likelihood that a potential supplier (hereafter, a vendor) is selected to be an actual supplier (hereafter, supplier) increases when personal connections between executives of the vendor and the customer exist. The magnitude of the effect varies predictably across management ranks and positions and is stronger when information asymmetries between a vendor and a customer are high. Conditioning on the existence of a supply-chain partnership, a departure of a personally connected executive prompts the termination of the supply-chain relationship more often than a departure of an unconnected executive. Additional analyses show personal connections are associated with less restrictive procurement contracts and with improved customer performance after the formation of a supply-chain relationship. Overall, our study highlights the role of personal connections in reducing information asymmetry and improving operating efficiency in the supply chain

    Growth mechanism and magnon excitation in NiO nanowalls

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    The nanosized effects of short-range multimagnon excitation behavior and short-circuit diffusion in NiO nanowalls synthesized using the Ni grid thermal treatment method were observed. The energy dispersive spectroscopy mapping technique was used to characterize the growth mechanism, and confocal Raman scattering was used to probe the antiferromagnetic exchange energy J2 between next-nearest-neighboring Ni ions in NiO nanowalls at various growth temperatures below the Neel temperature. This study shows that short spin correlation leads to an exponential dependence of the growth temperatures and the existence of nickel vacancies during the magnon excitation. Four-magnon configurations were determined from the scattering factor, revealing a lowest state and monotonic change with the growth temperature

    Preoperative Proteinuria Is Associated with Long-Term Progression to Chronic Dialysis and Mortality after Coronary Artery Bypass Grafting Surgery

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    AIMS: Preoperative proteinuria is associated with post-operative acute kidney injury (AKI), but whether it is also associated with increased long-term mortality and end-stage renal disease (ESRD) is unknown. METHODS AND RESULTS: We studied 925 consecutive patients undergoing CABG. Demographic and clinical data were collected prospectively, and patients were followed for a median of 4.71 years after surgery. Proteinuria, according to dipstick tests, was defined as mild (trace to 1+) or heavy (2+ to 4+) according to the results of the dipstick test. A total of 276 (29.8%) patients had mild proteinuria before surgery and 119 (12.9%) patients had heavy proteinuria. During the follow-up, the Cox proportional hazards model demonstrated that heavy proteinuria (hazard ratio [HR], 27.17) was an independent predictor of long-term ESRD. There was a progressive increased risk for mild proteinuria ([HR], 1.88) and heavy proteinuria ([HR], 2.28) to predict all-cause mortality compared to no proteinuria. Mild ([HR], 2.57) and heavy proteinuria ([HR], 2.70) exhibited a stepwise increased ratio compared to patients without proteinuria for long-term composite catastrophic outcomes (mortality and ESRD), which were independent of the baseline GFR and postoperative acute kidney injury (AKI). CONCLUSION: Our study demonstrated that proteinuria is a powerful independent risk factor of long-term all-cause mortality and ESRD after CABG in addition to preoperative GFR and postoperative AKI. Our study demonstrated that proteinuria should be integrated into clinical risk prediction models for long-term outcomes after CABG. These results provide a high priority for future renal protective strategies and methods for post-operative CABG patients

    Giant Preputial Calculus: The First Reported Case in Malaysia

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    Preputial calculus is a relative surgical rarity. It usually happens in elderly men with poor hygiene and uncircumcised penis complicated with phimosis. In the paediatric group, it is usually secondary to phimosis and other urologic and/or neurologic anomalies. Surgical treatment is the mainstay of treatment. Herein, we report a 27-year-old gentleman with preputial stone presented with obstructive uropathy and was successfully treated with surgical intervention. To the best of our knowledge, this is the first reported case of the largest preputial stone in Malaysia

    Partial Restoration of Mutant Enzyme Homeostasis in Three Distinct Lysosomal Storage Disease Cell Lines by Altering Calcium Homeostasis

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    A lysosomal storage disease (LSD) results from deficient lysosomal enzyme activity, thus the substrate of the mutant enzyme accumulates in the lysosome, leading to pathology. In many but not all LSDs, the clinically most important mutations compromise the cellular folding of the enzyme, subjecting it to endoplasmic reticulum–associated degradation instead of proper folding and lysosomal trafficking. A small molecule that restores partial mutant enzyme folding, trafficking, and activity would be highly desirable, particularly if one molecule could ameliorate multiple distinct LSDs by virtue of its mechanism of action. Inhibition of L-type Ca2+ channels, using either diltiazem or verapamil—both US Food and Drug Administration–approved hypertension drugs—partially restores N370S and L444P glucocerebrosidase homeostasis in Gaucher patient–derived fibroblasts; the latter mutation is associated with refractory neuropathic disease. Diltiazem structure-activity studies suggest that it is its Ca2+ channel blocker activity that enhances the capacity of the endoplasmic reticulum to fold misfolding-prone proteins, likely by modest up-regulation of a subset of molecular chaperones, including BiP and Hsp40. Importantly, diltiazem and verapamil also partially restore mutant enzyme homeostasis in two other distinct LSDs involving enzymes essential for glycoprotein and heparan sulfate degradation, namely α-mannosidosis and type IIIA mucopolysaccharidosis, respectively. Manipulation of calcium homeostasis may represent a general strategy to restore protein homeostasis in multiple LSDs. However, further efforts are required to demonstrate clinical utility and safety

    MPT0G413, A Novel HDAC6-Selective Inhibitor, and Bortezomib Synergistically Exert Anti-tumor Activity in Multiple Myeloma Cells

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    In multiple myeloma (MM), homeostasis is largely maintained by misfolded protein clearance via the proteasomal and aggresomal pathways. Histone deacetylase 6 (HDAC6) binds polyubiquitinated proteins and dynein motors and transports this protein cargo to the aggresome for further degradation. Accordingly, a combination of an HDAC6 inhibitor and bortezomib (BTZ) could increase ubiquitinated protein accumulation, leading to further apoptosis. Here we evaluated the anti-MM activity of MPT0G413, a novel specific HDAC6 inhibitor, using in vitro and in vivo models. MPT0G413 treatment more significantly inhibited cell growth in MM cells than in normal bone marrow cells. Furthermore, the combination of MPT0G413 and BTZ enhanced polyubiquitinated protein accumulation and synergistically reduced MM viability, increased caspase-3, caspase-8, caspase-9 levels, and cleaved poly (ADP) ribosome polymerase and also inhibited adherence of MM cells to bone marrow stromal cells (BMSC) and reduced VEGF and IL-6 levels and cell growth in a co-culture system. The combination treatment disturbed the bone marrow microenvironment and induced synergic, caspase-dependent apoptosis. Xenograft tumor growth significantly decreased in combination-treated SCID mice. In conclusion, MPT0G413 and BTZ synergistically inhibit MM viability, providing a framework for the clinical evaluation of combined therapies for MM
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